Doctors' Answers to "Frequently Asked Questions" - Drug Interactions (Page 1)

These comments are made for the purpose of discussion and should NOT be used as recommendations for or against therapies or other treatments. An individual patient is always advised to consult their own physician.

Drug Interaction - Calcium Channel Blockers and Digoxin
Question: Why are calcium channel blockers and Digoxin given together? Does Digoxin allows calcium to get into cardiac cells, and are calcium channel blockers supposed to prevent calcium from going in?

Answer: They affect different channels. Digoxin inhibits Na-K ATPase and increases Calcium entry by a sodium-calcium flux exchange. The calcium channel blockers directly affect the calcium channels, but different calcium channel blockers are more specific for smooth muscle channels. Currently, it is thought that diltiazem, verapamil and bepridil act on cardiac muscle. Concurrent use of verapamil with digoxin can significantly elevate digoxin levels and most of the calcium channel blockers and digoxin both can affect the AV node of the heart concurrently, causing bradycaurdia.

Drug Interaction - phenylpropanolamine and MAO inhibitors
Question: What is the drug interaction between phenylpropanolamine with MAO inhibitors?

Answer: Very Dramatic- Fast pulse, elevated blood pressure, flushing, and possible death with cardiovascular collapse. Don’t try this.

Drug Interaction
Question: Could you send me all of the serious side effects of the following four drugs taken together: phentermfine, zoloft, depakote and pondimin?

Answer: There is no published data on multiple drug interaction. The best that can be done is to extrapolate the side effects and toxicities-- the actual interaction between four is not able to be predicted. However, phenteramine and pondimin should not be taken with Zoloft or any other SRI antidepressant. This is due to the simultaneous effect on serotonin in the body by both drugs. Depakoke's common side effects include nausea, sleepiness, vertigo(dizziness). Zoloft tends to produce constipation, headaches, drowsiness, and urinary hesitation. Phenteramine andpondimin tend to produce dry mouth, constipation, sleepiness-- so I would think sleepiness and constipation might be fairly severe. Again, Zoloft is strictly not to be used with the combination of pondimin and phenteramine.

Beta-Blockers
Question: Is there a potential adverse interaction between beta-blockers and local anesthesia or IV sedation? Should these drugs be discontinued prior to elective surgery?

Answer: In theory possibly, in practice no. In fact, we usually don't discontinue the drugs due to some patients developing rebound sensitivity to epinephrine post use of beta drugs. They may be decreased but rarely stopped.

Drug Combinations
Question: I am currently taking the following medications and am concerned about the mix even though my doctor and my pharmacist assure me there are no problems. 100 mg zoloft, zestril, premarin, medroprogesterone, ambien (as needed), 500 mg hydrocodone (as needed), naprosyn, and phen-fen. I also take a multivitamin, B12, C, and E. I have only been taking the phen-fen for 10 weeks and will go on Redux for one month. I am 41 years old and weigh 230 lbs. I am down from 263 in 10 weeks. Depression also is a family trait, as both parents suffered from it as well as my maternal grandmother. I walk and am very active with gardening and I walk when I play golf which is about twice a week. Obesity runs in my family. Family members seem to die of cancer or diabetes. I do not smoke and am not diabetic. What do you think of taking this much medication? The naprosyn and hydrocodone are for arthritis as I broke several major bones when I was younger and sometimes find it difficult to walk after sitting in the car, etc. Sometimes after a round of golf, my ankles are swollen and extremely sore but I feel the exercise is important. I drink about once a week at social gatherings but do not become heavily intoxicated. I take the ambien usually during stressful times at work and, of course, never after drinking. I am a teacher and find that I do not need the ambien on Friday or Saturday evenings but only on school nights. Otherwise, I think of every detail of every word I will say the next day, every lesson plan, every parental conference, and every graduate class I take. I have been taking the ambien about 3 years.

Answer: I would recommend that your physician and pharmacist read the PDR. There is a strong relative contraindication between antidepressants and phen-fen or Redux. This is a combination that is potentially very problematic. Also, I would not be keen about ambien although there is not the warning seen with antidepressants and phen-fen.

Drug Interaction and Alcohol
Question: I'm taking hydrochlorothiazide, Zoloft, Xanex, and Amyril and I and am type-2 diabetic. Do I need to avoid alcoholic beverages?

Answer: Alcohol has several effects on a diabetic. 1. It is fermented sugar, and as such, is a major carbohydrate. You will need to decrease other carbohydrates with any alcohol ingestion. 2. It reduces inhibition and stimulates appetite so that it is difficult to keep on your diet. 3. It can decrease liver glucose release in some individuals. In general, a moderate intake-assuming you can keep your weight down is OK. However, few individuals can lose weight or keep it off with any alcohol intake.

Weight loss
Question: What side effects does the drug Redux have? What are the results that this drug is suppose to give and how will I feel with it's use?

Answer: Redux is fairly effective for weight loss. About 65% of patients experience weight loss which is very substantial. About 10-20% experience some loss. 10-20% don't seem to be helped. You will have dry mouth and constipation as the major side effects. Occasional patients have some other problems, but these are the common ones. There are reported risks of pulmonary hypertension and damage to heart valves. The exact risk is unclear, but both are serious and could lead to death or major cardiac surgery. As a consequence, I do not recommend these drugs for cosmetic loss, but only for patients with diabetes or elevated cholesterol who will definitely benefit from a loss.

Drug Interaction - Metrobamate / Ritalin
Question: Could the medication Metrobamate be taken on and off while one is taking Ritalin on a regular basis? My daughter has ADD and needs a short term antidepressant for PMS. I take this medication now on and off and it doesn't give any side affects. She does not want anything like prozac, etc.

Answer: Combining any antidepressant with Ritalin is tricky. There is no absolute contraindication, but I'd be reluctant especially in an on/off mode. It would be difficult to predict potential problems for something this complex.

Drug Interaction - Lipitor/ Levothyroxine
Question: I would like to know what type of interaction these two drugs have with each other. I take 20 mg of lipitor and 0.1 mg of levothyroxine. I have been on several cholesterol drugs. The lipitor is working my thyroid levels are dropping now at 0.56. I can't seem to find anyone that give me an answer on the interaction to these two drugs. Any help you might have I would appreciate it.

Answer: There is no interaction that I am aware of. There are potential interactions while taking erythromycin or equivalent drugs, digoxin, and some anti-fungals. I'm not aware of any interaction between these. You might have your physician call Parke-Davis scientific research. They will perform the research for free and usually come up with an answer. The number is: 800-223-0432.

Drug Combinations
Question: I am seeking an opinion of a drug combination which is consumed on a daily basis by a pre-op heart valve patient. The combination is Lanoxin (0.25 mg), Zoloft (50 mg), andLarazepam (1.5 mg). How safe is this combination for a valve-patient candidate? What side effects should be kept in mind?

Answer: Lanoxin is the brand name for digoxin, which is a common drug used for heart rhythms and occasionally for heart failure. This would be a common drug used in valve replacement patients since they tend to have irregular or fast heart beats. Zoloft is a serotonin reuptake inhibitor anti-depressant. This has little cardiac toxicity, but will generally be discontinued prior to heart surgery and restarted once the patient is stable. Larazepam is a benzodiazepine type of tranquilizer used to treat anxiety and other associated disorders. This is a fairly small dose. However, this drug should never be discontinued "cold turkey" since it can precipitate withdrawal symptoms.

Coumadin and Aspirin
Question: I had recent mitral valve replacement surgery. I am now trying to establish a proper coumadin level. I take aspirin (325 mg) and coumadin (10 - 15 mg) per day. My INR has been bouncing around quite a bit between 1.6 and 5. Can the combined effect of aspirin and coumadin be quantified?

Answer: Coumadin and aspirin are both used as anti-coagulants and are generally thought of as additive since they work on different aspects of the "clotting cascade". Coumadin works on different clotting factors made by the liver and aspirin on the platelets ability to clot. Measuring the TNR or PT will not take aspirins effect into account. This can be done by measuring "clotting time" a test rarely done unless a patient is persistently bleeding prior to transfusing platelets. The INR measures the anti-coagulant activity of coumadin and is thought to be more accurate that just using the PT measurement.

Drug Interaction
Question: My mother takes 250 mg of lamictal (soon to be 300 mg), 300 mg of dilantin, and 30 mg of paxil every day. About 25-60 minutes after she has taken her dosage (broken up 3 times a day) she becomes very agitated and extremely forgetful. She doesn't even know who her husband is. Usually within 60 minutes after that she will remember. Is this a side effect of any of these medications or maybe a combination of any of them?

Answer: It certainly seems to be. I would spread these medications out in an attempt to ascertain which one is the culprit. I would also take her blood pressure and pulse during the spells to decide whether this is a blood pressure problem with the medications or a primarily neurologic side effect.

Drug Interaction - Synthroid/Redux
Question: Is it safe to take Synthroid and Redux?

Answer: Yes.

Drug Interaction
Question: I am a 60 year old male. I take 5 mg of Norvasc and 25 mg of Atenolol every day for hypertension. I have been taking this dosage for about two years now. This takes care of that problem very well. Can these drugs affect my ability to maintain an erection?

Answer: All the blood pressure pills can give trouble with erections. Some with ejaculation as well. Discuss this with your physician and try omitting one of the drugs for a couple of days and see if the problem is better. Than you can try another pill or take a drug holiday when you are going to have sex. This will depend on your blood pressure off the pill for short periods. The norvasc will usually clear in 30 hours and the atenolol may take 40-48 hours to clear.

Drug Interaction - anti-depressants
Question: I take Prozac regularly. I used to take an occasional (once every 7-10 days ) amitriptyline. My doctor suggested taking both was not a good idea. It has been a year and 1/2 and I have been feeling worse and worse. Recently, I took the last remaining amitriptylines once a week for 5 weeks and felt better for 2 or 3 days afterwards. Is there any information that taking both of these medications causes any greater harm than taking only one.

Answer: Amitriptyline's antidepressant effect usually takes two to three weeks to be effective. One dose will help sleep and increase drowsiness, but have little effect on depression. All of the SRI drugs have specific warnings against concomitant use of these two classes together. While I have seen occasional patients use this combination, it cannot be recommended.

Pondimin and Phenteramine
Question: What are Pondimin and Phenteramine and what are their side effects?

Answer: Pondimin (fenfluramine hydrochloride) is an anorectic drug, as is phenteramine. Fenfluramine is a sympathomimetic amine which is in the same class as amphetamines, except they don't seem to produce the central nervous excitement as amphetamines, nor the addiction. The combination is used to treat weight loss and is effective about 75% of the time. Common side effects include drowsiness, dry mouth, constipation and occasional nausea. Few patients have trouble with the side effects. There is a reported association with pulmonary hypertension. This is a potentially fatal disease. Whether these drugs have anything to do with this problem is currently unclear but under intense research.

Drug Interaction - Coumadin/Lanoxin
Question: What is Coumadin? Is it possible to have a drug interaction between Lanoxin, which I have been taking for several years, and Coumadin? If so, would severe heart palpitations be a possible indicator of this drug interaction?

Answer: Coumadin is a blood thinner used in multiple medical situations. I am not aware of any drug interaction between Lanoxin and Coumadin, although Coumadin has interactions with many drugs. The palpitations may indicate high or low levels of Lanoxin.

Drug Interaction - Alcohol/Antibiotics
Question: Can consumption of alcoholic beverages while taking antibiotics cause any short or long term medical problems?

Answer: About the only antibiotic that is a problem is Flagyl (metronidazole). The chemical structure of metronidazole is similar to Antabuse. This is a drug used to make alcoholic dependent patients ill when they ingest alcohol. Taking Flagyl with alcohol will have this similar effect.

Drug Interaction
Question: I have been given Augmentin twice. First, 3 years ago for dog bite and I became violently ill with vomiting, diarrhea, dry heaves, and joint pain. I was then given another choice of antibiotic for resistant sinus infection. I became sick within 1 hour after taking the Augmentin and 36 hours later I was still weak with joint pain, and running a low temperature. I was then given a new prescription of SMZ-TMP ds tab. If I have had Amoxicillin twice in the past month with no side effects would it be the clavunate I am reacting to?

Answer: Common side effects of Augmentin are GI intolerance. This is usually not a true allergic reaction, but instead, a local effect. The joint pain may be another story. TMP/DS is a combination of trimethoprin and sulfa. Sulfa drugs are notorious for causing allergic reactions and trimethoprin much less so. It sounds like you may be allergic to the sulfa and probably not to the Augmentin.

Drug Interaction - Zoloft/Midrin
Question: Can Zoloft be taken in conjunction with Midrin. If not, what migraine medication is safe to take with Zoloft?

Answer: Midrin is a sympathomimetic amine used to constrict arterioles. While I'm not aware of any specific contraindication, I'd be leery of combining the two. I'd stick to Tylenol with Codeine while on Zoloft. Also work on preventive measures like Beta-blockers to minimize the number and severity of your migraines. Other medications like Imitrex, etc., would also be possibly risky.

Drug Interaction
Question: Are there documented Adverse Drug Reactions when SSRIs are used concurrently with fen-phen.

Answer: I’m not aware of concurrent studies of the two drugs. I’m personally not a fan of using other drugs in concurrence with the Fen-Fen type of drugs until further experience is gained. The FDA collects the Adverse Drug Reactions, which are available. You might want to contact them for specific cases. Be advised that filing of and ADR does not necessarily imply casualty.

Drug Interaction with Propulsid
Question: My husband is taking the drug Propulsid for GERD. He is also taking Prisolec, Ultram, and Zocor. Are there any precautions for taking this mixture of drugs? I have read articles on Propulsid, but cannot find where this mixture would be life-threatening.

Answer: Propulsid should be avoided in conjunction with macroglide antibiotics (erythromycin, etc.), ketoconazole (an antifungal antibiotic), and similar antifungals. Taking this drug with cimetidine has been reported to elevate serum levels also (not with other H2 blockers). I know of no specific contraindication with Ultram or Zocor.

Drug Interaction
Question: I am on a doctor’s prescription for taking 125 mg Dilacor, 0.125 mg Synthroid and Proscar. Will there be a problem if I take Advil for muscular aches? Will there be any problem if I take an antacid close to the time of taking the others?

Answer: There is no obvious problem with this combination. I would space out the antacid though.

Drug Interaction
Question: I currently take a few levsin tablets sublingually during the day and 30 mg of Elavil/amitryptine each night. My physician said I could take a small amount of valium every so often at bedtime. In your opinion, how much of the diazepam/valium is OK to take? Levsin is the only drug I've ever taken for my chronic IBS that actually works somewhat, and my physician feels that it will have a synergistic effect with the Elavil.

Answer: Your physician is probably right about the synergistic effect. Valium and similar drugs seem to have the same effect on Irritable Bowel Syndrome. We try to minimize the amount due to the addictive potential of benzodiazepines (like Valium). I would take it when your IBS flares up and try not to take it on a daily basis.

Manic Depression and Lithium
Question: I was recently diagnosed with Manic-Depressive Disorder, Borderline Personality Disorder, and Major Depression. The psychiatrist I am seeing first prescribed 20 mg of Prozac and 50 mg Trazadone. On my last visit, he increased the dosage of Trazadone to 100 mg and prescribed Lithobid (300 mg) twice a day in addition to the Prozac (20 mg). It is normal to be taking all 3 of these drugs at the same time? What are the combined side effects? I have read that most patients on Lithium have blood chemistry monitored. However, the doctor has not made any arrangements to have my blood work done. Should I be concerned?

Answer: This combination of drugs is pretty common with the diagnosis that you have provided. Lithium is a drug that can be very toxic. Consequently, normal use dictates an occasional check of blood levels, blood sodium levels and thyroid levels. This is the minimum monitoring needed for this drug. The other two need less blood work monitoring.

Drug Interactions
Question: My fianc�’s sister is recovering from a stroke. We are concerned about the number of drugs the different doctors have prescribed and any possible problems with interactions between the drugs. She is 48 years old, 5'6" and 130 lbs. She was a long-term smoker of both cigarettes and marijuana. She has suffered from depression in the past. She is currently taking the following:
Verapamil 240 mg 1 QHS
Vasotec 10 mg 1 Q a day
Coumadin 5 mg a day
Ritalin 10 mg 7 am and Noon
Catapress patch 0.3 mg for 10 weeks
Prozac 20 mg 1 Q a day
PremPro 1 daily days 1-25% mouth
Folic Acid l mg Q a day
Azulfidine Entabs 2 times a day
1 Centrum Vitamin Q a day
Is anything here a problem with either being excessive together or effecting the efficacy of other medications?

Answer: It sounds like the cause of the stroke was elevated blood pressure. Three of the drugs listed are for blood pressure. Ritalin is the only unusual drug listed here. This can elevate blood pressure and is an odd combination with the others.

Drug Interaction
Question: Is there a drug interaction chart to be checked before any prescription?

Answer: Each drug has a separate list of potential drug interactions. Certain specific drugs like heparin, coumadin, and certain antibiotics have lists of possible interactions. The best overall source is a good pharmacy text like Goodman and Gilman (The Pharmacological Basis of Therapeutics) or the Physicians Desk Reference.

Drug Interaction
Question: I have been taking 20 mg of Prozac daily for depression. Yesterday, my doctor prescribed 10 mg of Elavil at bedtime for fibromyalgia. Is this OK? Why didn’t he just increase the Prozac since it is a serotonin reuptake inhibitor? Is there an interaction between Prozac and Elavil?

Answer: Elavil has a different effect on sleep than the SRIs do. In particular, it increases Stage 4 sleep, necessary for deep muscle relaxation. SRIs do not produce this and may decrease Stage 4 sleep. This is the best current treatment for fybromyalgia - to increase muscle relaxation by increasing stage 4 sleep.

Drug Interaction
Question: I am interested in learning if the concomitant taking of ibuprofen and Coumadin has any adverse effects. For example, increasing or decreasing the anticoagulant effect of Coumadin.

Answer: Non-steroidal anti-inflammatories and aspirin should not usually be taken with Coumadin since they will increase the risk of bleeding and block the ability of platelets to clot with any blood. They do not change the effect of Coumadin but, affect the coagulation cascade at a different point increasing the difficulty in clotting. They also are common causes of bleeding from the GI tract.

Drug Interaction
Question: I am currently taking prozac and trazadone. I was wondering if there would be any interactions if I were to start taking a birth control pill?

Answer: I wouldn’t expect any, but some women experience mood alteration on hormone treatment, with or without the other drugs.

Drug Interaction
Question: I know there is a problem taking Redux or Phen-fen with Prozac. What about taking those drugs with Effexor, Lithium, or Olanzapine?

Answer: Redux(dexfenfluramine hydrochloride) and phenteramine/fenfluramine are appetite suppressants. They have been used for the past several years to aid in weight reduction after publication in JAMA of an article and subsequent follow-up articles detailing the weight loss potential of this drug with very few side effects. These drugs are indicated for weight loss necessary to correct or improve the treatment of hypertension, diabetes mellitus, elevated cholesterol, with a body mass index of 27 or no risk factors and a body mass index of 30. Body mass index is arrived at by dividing your weight in pounds by your height in inches. These drugs should not be taken with MAO inhibitors, Imitrex (used for migraines), while pregnant, with anti-depressant drugs of any variety, especially SRI inhibitors, if glaucoma is present, or if under 18. Usual dosage of Redux is 15 mg twice a day. Ionomin's dosage is 15 mg once a day, and 30 mg if the individual is unresponsive. Pondomin's dosage is 15 mg three times a day, but this can be increased to 30 mg three times a day (t.i.d.). These drug regimens do not appear to be addictive currently. The biggest risk appears to be pulmonary hypertension. This is increased with taking these drugs and can lead to death, so it is not taken lightly. This appears to be an unusual but serious side effect. Common side effects for most patients are dry mouth, constipation, diarrhea, and drowsiness.

I have had a lot of success with these drugs. Redux is easier to take, but may not be as effective. Ionomin and Pondimin are a little more effective, but less convenient and slightly more costly. The weight loss tends to return after the medicines are discontinued. They are usually effective in about 80% of my patients. I have major concerns about pulmonary hypertension and I do not prescribe these drugs until all the risks are laid out and only for high risk patients.

I'm not aware of any special risks with Effexor, Lithium, or Olenzapine. However, I usually do not use these drugs with any other CNS drugs due to the interactive problems.

Drug Interaction
Question: I'm going to enter the school of pharmacy in near future. I have a question about this following situation: A child, 7 years old, has been prescribed erythromycin by his general pediatrician to treat a bacterial pharyngitis for a 10 day course of therapy. The child has a history of urticaria reaction to amoxicillin. The child is also monitored for his asthma by a pediatric pulmonologist. The child is presently taking a medication called theophylline, a bronchodilator, prescribed by the pulmonologist. How would I handle this situation?

Answer: Erythromycin is not related to penicillin or amoxicillin, being a macroglide. However, it can change the levels of theophylline and the child needs their level watched closely or their dose decreased.

Zoloft and doxepin interactions
Question: I am a 31 year old woman with chronic dysthymia and episodes of major depression which seem to be constant for the past 3 years when untreated. I also suffer from fibromyalgia, among other things. I am exquisitely sensitive to medications, often showing toxic reactions and extremely low doses. For the past 3 years I have been treated with Zoloft for the depression (as well as episodes of hypomania) - recently at 75 mg/day, up from 50. For two days I took approximately 5 mg of doxepin at night for the fibromyalgia. The pain disappeared immediately, but I slept all day. At the same time, I became extremely depressed, falling deeply into a major depressive state. I discontinued the doxepin due to the sleeping effects, and continued to be extremely depressed and non-functional for the next several days. But this seems to have gradually subsided on the fourth and fifth day since discontinuing the doxepin. Is it possible that some sort of drug interaction created this depression? I don't usually come back out of them like this. I am also on Risperdal alternating 50 mg/day and 75 mg/day for psychotic symptomatology, and Depakote at 1000 mg/day for temporal lobe seizures and mood disturbances.

Answer: Zoloft and doxepin(or any tricyclic) are hard to mix. The results tend to be variable and hard to predict. There clearly was an interactive problem with one of your medications. It is hard to tell whether zoloft or the depakote or the risperdal caused the problems. In any case, I'd avoid it-or try eliminating one medication at a time with doxepin. It seems like forgetting the doxepin is the best plan.

Drug Interaction
Question: Could you tell me if any of these drugs will not interact: Furosemide 40 mg, mondopril 10 mg, potassium 20 mg, lanoxin 0.25 mg, rezulin, glucophage 500 mg, insulin novalin, Prilosec 20 mg, atenolol 50 mg, and niroglyewn 2 mg.

Answer: This is a pretty standard list for a diabetic with heart failure or hypertension. There can be interactions particularly concerning potassium and renal function. However, monitoring with blood tests will detect these problems. That would be the major consideration.

Drug Interaction
Question: I would like to know if Prozac and Obenix can be taken together. I have taken Obenix in the past, but I am presently taking Prozac and would like to begin the Obenix again.

Answer: This is a combination to be avoided. This is because both medications work on the serotonin levels in the brain. One of the relative contraindications is SRI anti-depressants with phentermine or equivalent.

Drug Interaction
Question: My friend is currently on wellbutrin and wants to start taking phen-fen again, which she was on before the wellbutrin. Can these 2 drugs be used together. Her new pharmocologist is not sure and recommends against it, while her old one says its all right.

Answer: Redux (dexfenfluramine hydrochloride) and phenteramine/fenfluramine are appetite suppressants. They have been used for the past several years to aid in weight reduction after publication in JAMA of an article and subsequent follow, up articles detailing the weight loss potential of this drug, with very few side effects. These drugs are indicated for weight loss necessary to correct or improve the treatment of hypertension, diabetes mellitus, elevated cholesterol, with a body mass index of 27 or no risk factors and a body mass index of 30. Body mass index is arrived at by dividing your weight in pounds by your height in inches. These drugs should not be taken with MAO inhibitors, Imitrex (used for migraines), while pregnant, with anti-depressant drugs of any variety, especially SRI inhibitors, if glaucoma is present, or if under 18. Usual dosage of Redux is 15 mg twice a day. Ionomin's dosage is 15 mg once a day, 30 mg if the individual is unresponsive. Pondomin's dosage is 15 mg three times a day, but this can be increased to 30 mg three times a day. These drug regimens do not appear to be addictive currently. The biggest risk appears to be pulmonary hypertension. This is increased with taking these drugs and can lead to death, so it is not taken lightly. This appears to be an unusual but serious side effect. Common side effects for most patients are dry mouth, constipation, diarrhea, and drowsiness.

I have had a lot of success with these drugs. Redux is easier to take, but may not be as effective. Ionomin and Pondimin are a little more effective, but less convenient and slightly more costly. The weight loss tends to return after the medicines are discontinued. But they are usually effective in about 80% of my patients. I have major concerns about pulmonary hypertension and I do not prescribe these drugs until all the risks are laid out and only for high risk patients. Regarding Wellbutrin, I would not mix these combinations. Wellbutrin is a complete separate class of anti-depressants, but one is not to mix the SRI anti-depressants with phen/fen.

Drug interaction
Question: If lasix and primacor are given in the same i.v. line, what kind of action takes place in the body?

Answer: Primacor is a relatively new drug used in heart failure. It is a peripheral vasodilator as well as an inotropic agent (makes the heart beat stronger). It should not be used in patients with severe aortic or pulmonary valvular disease and can aggravate problems in patients with cardiac outflow obstructions. Use with diuretics like lasix should be performed with caution since over diuresis can decrease cardiac filling. In general practice, this is not usually a problem and these two drugs are commonly used together.

Lopressor and Phendimetrazine
Question: Can a patient take lopressor and phendimetrazine?

Answer: Lopressor is a trade name for a medication known as metoprolol tartrate, and is in the class of medications known as "Beta blockers". Its uses include but are not limited to patients suffering from coronary artery disease, to hypertension, to anxiety conditions. Phendimetrazine is a combination medication and contains premarin and meprobonate. Both premarin as well as meprobonate can have depression effects, and lopressor can as well. Thus, if you are on both of these medications, keep in touch with your physician regularly and be sure to make them aware of any "blue moods" or depressed feelings you may be experiencing. Both of these medications can have heart effects as well, although these are less commonly seen in patients taking phendimetrazine. Although the intent of taking lopressor is to have a heart effect, these effects can be magnified or suppressed by the phendimetrazine. Your symptoms, and your tolerance of these medications will help your physician decide as to whether this medication regimen is benefiting you, without undue side effects.

Drug Interaction
Question: I have a family member who takes a lot of drugs for different conditions and I am wondering about the safety of taking all these drugs together. The drugs are: Lopressor for high blood pressure (.5 mg/day) Synthroid (.05 mg/day) Uriset for interstitial cystitis (8 per day) Darvocet (3-4/day as needed for back pain) Lomotil (for spastic colon, 1 per day) Zantac (prescribed dose as needed) Premphase (1 per day) Xanax (1 mg pills as needed) Lodine or Napralene (as needed).

Answer: That certainly is an imposing list of medications. First, predicting drug interactions only works with two drugs. There are geometrically rising interaction possibilities as the number of drugs rises. Consequently, there is no clear way to predict the interactions of three or four drugs short of giving them to a patient. I will say that there are some possibilities in your list. First, Uriset, Lomotil , Darvocet and Naprosyn all potentially effect the motility of the colon. Darvocet, Xanax and Lomotil all potentially have CNS effects. Having said this I doubt any serious interactions if the doses are kept limited.

Drug Interaction
Question: Is someone who is taking Esgic Plus and Vicodin e.s. together being affected in a manner similar to the way Fiorinal III would affect a patient? I know someone who is using this combination over a period exceeding 14 months.

Answer: Esgic plus is a combination of butabital, acetaminophen, and caffeine. The difference between esgic and esgic plus is merely extra tylenol. As such, Esgic is the same formulation as Fiorninal and would have the same side effects.

Tamoxifen & Zantac
Question: I am currently taking Tamoxifen 10mg bid and have been prescribed Zantac. I have read somewhere about the possible drug interaction with Tamoxifen and Zantac whereas the Zantac causes the Tamoxifen's effectiveness to wane. Please provide me whatever information you can or where I can find it again.

Answer: Not aware of this, and it is not mentioned in the PDR. You might contact Zeneca 302-886-8000 and ask the manufacturer.

Claritin & Penicillin
Question: Have their been any substantiated or unsubstatiated claims of adverse drug interactions between claritin and penicillin?

Answer: Claritin is the brand name of the generic medication loratadine, and is used for its antihistamine effects in the treatment of allergies. Any medication that can effect liver metabolism of this medication can alter its blood level. Penicillin is cleared predominantly by the kidney and the Physician’s Desk Reference does not list penicillin as a medication to be avoided in patients on claritin. However, whenever you are taking medications, in particular multiple medications, follow up with your physician on a regular basis is important, so as to assess the response you are having from the therapy, as well as to determine if any drug interactions or side effects are occurring.

Adipex
Question: If used along with blood pressure med can it cause lightheadedness?

Answer: Adipex is the brand name of a medication known as phentermine, and has been used in the treatment of obesity as a part of a weight loss regimen. Firstly, recent data published in several sources have reported the risks of taking this medication, particularly when it is used in conjunction with other weight loss pills. For this reason, you should see your health care provider to discuss whether you should stay on this medication, or discontinue it. With respect to “light headedness”, there are many possible causes for this symptom. The initial evaluation of dizziness involves a detailed history. Does the dizziness occur when standing, for example, upon getting out of bed in the morning, or out of chair. Does the dizziness come on with meals, or with rapid position changes of any kind, or at certain times of day? Is there any relationship between the time of taking medications and the time you experience dizziness? Are there any other medical conditions you may have that can also cause dizziness? A thorough physical examination is important in evaluating the patient who complains of dizziness, as well. The Physician’s Desk Reference does list low blood pressure as a possible side effect of this medication. As you are already on another drug to lower your blood pressure, your symptoms may be due to excessive lowering of your blood pressure. However, bear in mind that there are many possible causes for dizziness. You should make your health care provider aware of your symptoms. He or she knows your medical history and conditions best, and can evaluate you for what may be causing the dizziness, with a thorough history and physical, as well as any additional testing that he or she feels is necessary.

Split Personality
Question: Could a combination of Demerol or morphine, wiith aprazolam,lorazepam or lectopam-prescribed in high doses over a prolonged period of time, cause psychosis of a type that could result in personality splitting?

Answer: No.

Ziac & Premarin
Question: I am currently taking Ziac 10 and Premarin 0.625mg daily,I am very fatigued, some days light-headed and have very bad indigestion and just generally feel bad could, these be side effects of these drugs? I am 57 years old.

Answer: Ziac is a combination of a beta blocker and a diuretic. Beta blockers are notorious for causing nausea. Whether the lightheadedness is or not is problematic. I'd discuss this with your doctor and try a short holiday(under supervision).

Maxzide & Cozar
Question: Is there a possibility of hyperkalemia from the use of Maxzide and Cozar concomitantly?

Answer: Most certainly-potassium sparing drugs should be closely monitored with the class of ACE inhibitors to avoid hyperkalemia.

Contin & Ativan
Question: I have been taking 2 ms contin 60mg 3 times a day. I have been on this dosage for about 1 year. Now because of other problems that I have been getting my doctor has prescribed me to take 1 mg of Ativan 2 times a day. I was just wondering if there were any side effects on taking both of these drugs at the same time? Also is these any side effects in the long run if I have to be on the Ms contin for over 10 years? Is the Ms Contin addicting and is the Ativan addicting? Please respond I really need to know. All my thanks in advance.

Answer: Both MS Contin and Ativan are addicting and in somewhat different ways. There will be additive sedation and lethargy with the combination of these two drugs-depending somewhat on how much tolerance you have with the MS Contin. Other than addiction, there does not appear to be long term side effects of taking morphine continuously.

Paxil & Serzone
Question: Are either Paxil or Serzone connected to weight gain. I was on paxil for six weeks and presently on serzone, not even a full week yet. I ride my bike at least 10 miles per day four days per week but have not lost a lb. I've been riding since April.

Answer: On the package warning/labeling it specifically warns about weight loss. In practice, about 75% of my patients gain weight on paxil or Serzone-about 10-15% lose weight. You'll need a different antidepressant than the SRI class. Some have better luck with St. John's Wort;but, it doesn't seem as effective on depression.

Atenolol & Lescol
Question: What is the interaction of Atenolol and Lescol ?

Answer: None that I am aware of.

Multiple Medications
Question: I am taking a number of medications for heart failure and angina. I am also using medications for diabetes. For the past two months I have been experiencing stomach upset and nausea almost every day. Some days I have also experience vomiting would like to know if this could be as a result of an interaction between the medications that I am taking, or as a result of a worsening of my heart failure. Here is a list of the medications that I am currently taking. Lanoxin, Zestril, Atenolol, Lasix, Metformin, Insulin, Aspirin and a number of vitamins.

Answer: Of the medications you are taking lanoxin is notorious for GI toxicity. This can be simply checked with a drug level -if not particularly elevated probably not the cause. Aspirin can also cause gastritis. Lastly, diabetes mellitus can affect the nerves responsible for the motility of the GI trct causing these same symptoms.

Zoloft & Zyban
Question: Is there a drug interaction between Zoloft and Zyban? Seems to me like there could be a problem here but I have not found any data to support this.

Answer: None that I'm aware of;but, Zyban has only been available a short time-come back in a year for a recap.

Mom's Multiple Medications
Question: My mother is 82 years old and received a right hip transplant on August 4, 1997. She is in a Manor Care rehab facility near Cleveland, Ohio, USA. She spent 3 weeks in the hospital, Euclid-Meridia, and then went to Manor Care which owns Vita Link pharmacy services. Her rehab is progressing slowly due to the fact that her hip was not recently broken but deteriorated slowly over a period of 3 or 4 years, during which time she "hedged" on getting an operation. Further impediments to rehab include overweight and other arthritic pains in her shoulders, knees etc. Upon visiting her on September 22, 1997, I noticed an unusual state of confusion in her. I have noticed this state come and go since then. As of Oct.2, she is receiving: pilostat trusopt (above 2 for glaucoma) Colace 2x day hydrochlorthiazide 25mg daily (?prescribed prior to surgery) antivert 12.5 mg/3x daily (prescribed prior to the surgery) propulsid 10 mg before meals & bedtime (changed Oct.1 to ????) metamucil tablespoon daily zoloft 25 mg daily multivitamin doxycycline 100mg po 2xday 14 days antibiotic for cellulitis in LEFT lower leg low or no salt diet drugs used but discontinued after surgery include biaxin, ultram, and robitussin has a chronic and severe cough attributed to asthmatic bronchitis, has a rash on both sides of bridge of nose, is overweight while visiting on previous occasions I encountered 2 things: [1]a psychologist, "xxxx" and a psychotherapist, "xxxxx" (?both associated with University Hospitals in Cleveland) questioning her on subjects related to depression on two occasions during the interview, xxxxx misinterpreted her answers, due to her heavy Lithuanian accent, and offered to prescribe anti-depressants and sleeping pills I do not recall the first incident's details (wherein a pill that will improve her mood was offered...) but the second incident went something like this: "Do you have trouble sleeping/falling asleep?" "Yes, I start falling asleep and my cough wakes me up..." " I am going to prescribe a sleeping pill..." I then said "Won't a sleeping pill just mask the symptoms of her cough?...", meaning that the causes of the cough should be treated first...I believe that they did not prescribe anything that day. Minutes later I learned that a doctor, xxxx (?associated with Euclid-Meridia ) had prescribed an antidepressant the PREVIOUS DAY. Upon encountering xxxx a week later, she appeared to be startled that another person prescribed a drug related to her particular interests. [2]While I was out of view of the hallway, my mother was talking to me in Lithuanian. Suddenly, a nurse appeared and asked: "Did you say your stomach hurts?". Apparently some combination of Lithuanian words came out as a statement about stomach pain. This language problem can lead to some unique problems...Tues. Sept 30, she did not eat very much. At 2pm she vomited. That night she vomited throughout the night. A sample, appearing to contain blood was put aside. Wed. Oct.1, Dr. xxxx saw her, prescribing no solid food and a glucose IV. Are drug interactions playing a part in this case? Are blood and other tests indicated? Today, Oct.2, I called and it appears that her fluid and electrolytic balance has not been checked recently.

Answer: Geriatric patients who have multiple medical problems and are on multiple medications require a high degree of insight to figure out the best options. This can be done by a physician who has seen her before, a geriatrician or an internist. The setting of the nursing home is not the best option for diagnosis and treatment. A physicians office would be better. Did she have an Internist during her hospitalization? Check with them.

Cipro, Desogen, & Albuterol
Question: Is there anything I should know before taking Cipro while on Desogen and using the Albuterol inhaler?

Answer: Shouldn't be any reaction here.

Lotension, Lanoxin, Lopressor, Dyazide, & Coumadin
Question: Are there any drug reactions/interactions among the following: 40 mg lotension, 25 mg Lanoxin, 50 mg Lopressor, 37.5/25 dyazide, coumadin which usually varies from 2.5 - 5 daily. My husband takes the above drugs daily, and is often dizzy, and has had several episodes of feeling like the shower, desk, etc. Has turned upside down. He also has relative erythrocytosis. Numerous tests have shown no heart blockages. Could this combination of drugs be causing this.

Answer: Possibly, but, he must have pretty significant coronary disease to be on this combination. Hard to tell how much is drugs and how much his original condition. Lanoxin and lopressor would be the most likely candidates if it is the drug combo. Has he been monitored when he has these symptoms? This would give you the answer to the cause(that is cardiac or non-cardiac). Also, what is his blood pressure? I suspect fairly low with this combination.

Lanoxin & Lasix
Question: Are there any interactions between lanoxin and lasix?

Answer: No direct interaction. A lowering of potassium(caused by lasix) could potentiate arrthymias due to lanoxin. Otherwise, nothing I'm aware of.


Back to Drug InfoNet Home Page.