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Drug & Nutrient Interactions




  1. My nephew who has leukemia. Could you please tell me if any foods should be avoided while is taking the following medications? Answer
  2. I have read that Dilantin interferes with the absorption of many vitamins that I need. Answer
  3. Where can I find a dietitian who can help me plan my diet so it doesn't include foods that interfere with my medications yet is healthy? Answer
  4. I refer my patients to registered dietitians especially if I know their insurance will cover the visits. Answer
  5. I do want to clarify something about Depo-Provera. It does not seem to confer many benefits to your cholesterol profile. Answer
  6. Hydrazine is not approved by the FDA, but is used in Russia to fight cancer and is available without a prescription there. Answer
  7. My mom just started taking hydrazine sulfate today for her cancer. What foods contain Bovril or Marmite and what exactly they are? Answer
  8. My Mom is currently on medication that can possibly cause liver damage. Could you please advise me as to what and how I should be preparing her meals? Answer
  9. What are the effects of weight gain-taking Depo-Provera (sp.)? Answer


  10. I take Dipentum for ulcerative colitis. What nutrients are being effected by this drug? Answer
  11. My boyfriend is taking a pill called Parnate and his doctor gave him a list of foods not to eat. Answer


My 18 year old nephew was diagnosed with juvenile leukemia last week. Could you please tell me if any foods should be avoided while taking the following medications? My sister needs this information and we do not know where to find it. Any help you can offer is greatly appreciated.

  • Prednisone - orally 3 times a day for 28 days
  • Vincristine - IV on day 1,8,15,22
  • L-asparaginase - injected into muscle tissue on days 2,5,8,12,15,19
  • Daunomycin - IV on days 8,15,22

Your sister and her son should ask any questions they have about treatment drugs with his doctor. Also your nephew should tell his doctor about all drugs, prescribed and over the counter including supplements (vitamin, mineral or herbal) that he takes as they could interfere with his treatment. The hospital or clinic that your nephew goes to should have a dietitian who can read his chart and work with his doctor. In the meantime, here is some nutrition related information about the drugs you listed:

  • Prednisone is a steroid which should suppress your nephew's immune system. Generally, it stimulates a person's appetite which would be good to counter the effects of the 3 chemotherapy agents below. Depending on the dosage (>30 milligrams per day), it can cause a person's blood sugar and blood pressure to go up. But no foods are omitted unless he develops high blood sugar or high blood pressure.
  • Vincristine is a chemotherapy agent used to treat his leukemia and lower his high white cell count. He should drink plenty of fluids to reduce any side effects to his kidneys. Alcoholic beverages are not recommended. He should eat foods with fiber (whole grains, fruits and vegetables) to prevent constipation. This drug can affect the nerves in the intestines causing the GI tract to slow down which can result in constipation. Nausea, vomiting, diarrhea and weight loss may occur with chemotherapy drugs. It may help nausea and vomiting to not eat for at least 2 hours before a chemotherapy treatment dose so that his stomach is empty. Ask his doctor. Your nephew will need his dietitian to help him with specific eating or food suggestions to help him through these temporary symptoms. This drug can also increase his risk of developing infections so he should wash his hands well and avoid contact with people who are sick (coughing, sneezing, colds or flu).
  • L-asparginase is another chemotherapy drug. Drink plenty of liquids while taking this drug unless his doctor instructs otherwise. Ask his doctor about any interaction between asparginase and prednisone.
  • Could not find any information about Daunomycin. Did you mean Daunorubicin? Your nephew should drink plenty of liquids to help prevent increased uric acid in the blood. This medication may turn his urine a reddish color and should not be mistaken for blood in his urine.
If he develops sores or pain in his mouth, make sure he brushes with a soft brush and eats soft foods (cooked meat, starches and vegetables, canned fruits and fruit juices as well as dairy products). Good luck through this difficult time.


I have read that Dilantin interferes with the absorption of many vitamins that I need. If I take my vitamins early in the morning after I eat and then about an hour later take my Dilantin and Phenobarb, will the vitamins be absorbed? If not, what can I do? Will eating certain foods such as brewer's yeast be absorbed even though I am taking Dilantin.

Appreciate your reply. Thank you so much.

Taking Dilantin does interfere with vitamin D metabolism. Talk to your doctor about regular bone density testing to identify osteomalacia which is a softening of the bone due to the loss of calcium from bone.

Take your vitamins with meals to improve absorption and not at the same time as Dilantin. Try to take vitamins either 2 hours before or 2 hours after you take Dilantin. Make sure you are eating 3 servings per day of foods rich in calcium and vitamin D like milk and cheese.


I am on a lot of medications and some say I can't eat a particular food. Where can I find a dietitian who can help me plan my diet so it doesn't include foods that interfere with my medications yet is healthy?

The Medical Nutrition and Nutrition Entrepreneurs dietetic practice groups of the American Dietetic Association provide medical nutrition therapy based on your diagnosis, prescribed medications and supplements. Dietitians often have their own private practice nutrition counseling services in addition to services provided in a clinic or hospital. You can find a dietitian at the American Dietetic Association. Include your zip code or city / state, the type of service you want (individual consultation) and expertise needed.


As far as referring my patients to registered dietitians, I have never hesitated doing that, especially if I know their insurance will cover the visits. However, some of these patients are self-pay and unable to pay for those visits. What other resources can I refer these patients to, besides giving them the simple Food Guide Pyramid?

Great to hear you refer your customers to see a dietitian. Whether or not people have health insurance though, I would still refer people with nutrition or food problems to a registered dietitian at their local clinic or hospital. The local dietitian would be the best source in their area for nutrition services with or without insurance. Insurance coverage for nutrition services depends on the insurance coverage and third party coverage is pretty good for diabetes and kidney disease nutrition therapy.

Often the public health department, county or university extension office, EFNEP (Expanded Food and Nutrition Education Program) and WIC (Women, Infant and Children) are good state and federally funded programs available to various populations. Many of these programs have developed educational materials that address their target population's nutritional concerns, but they don't deal with nutrition therapies.

Your intent is good and I would provide the Food Guide Pyramid. However, they are developed for a general population and don't address the complex nutrition needs of people requiring nutrition therapy for control of chronic diseases like diabetes, high blood pressure and high cholesterol or triglycerides. Nutrition is an integrated science like pharmacy (drug - drug or drug - food interactions) and most answers to nutrition problems are not solved with a list of what to not eat. When a person makes an appointment for another disease like diabetes, often a dietitian can assess a nutrient deficiency or excess when taking a person's food history.

If they have Internet access, I would point them to the American Dietetic Association or any web site managed by a registered dietitian for sound nutrition advice. Forewarn them that nutritional or herbal supplements are no substitute for a healthy eating plan and adequate exercise as well as preventative health measures like an annual physical, Pap, mammography or prostate tests as well as dental cleaning every 6 months.


I wanted to let you know how much I've enjoyed reading your answers. I am a pharmacist who frequently works with patients with high cholesterol and often have to explain certain things to patients about their diet. I am always looking for new ways to help encourage patients to stay on a healthy balanced diet and find that resources like your website is incredibly helpful.

I do want to clarify something about Depo-Provera. Because it is a progestin, it does not seem to confer many benefits to your cholesterol profile. Estrogen on the other hand, has been shown to reduce LDL (low density lipoprotein), increase HDL (high density lipoprotein), not much decreasing of triglycerides and sometimes may actually increase triglycerides in some women. In women who take low-dose estrogen (such as Premarin 0.625 milligrams for hormone replacement therapy after menopause) along with a progestin (like Provera 2.5 milligram tablets), the progestin may actually block the beneficial effects of estrogen on cholesterol.

Thanks for the feedback. I frequently tell visitors to ask their pharmacist about various prescribed and over the counter drugs.

You might also want to encourage your patients to contact a registered dietitian at their doctor's clinic or local hospital for more info about lowering cholesterol. Explaining a nutrition therapy to lower cholesterol is more than just a list of what to eat or not eat. Patients need help on how to integrate their likes and dislikes as well as help with what constitutes a balanced eating plan.

Several online sources I checked said that Provera is available as oral tablets in 5 - 10 milligrams of exogenous progesterone for 5 - 10 days (brand names Amen, Curetab, Cycrin, Prodoxy-10, Progesterone, Provera). These sources also state that there is an aqueous suspension for intramuscular administration for endometrial or renal cancer in dosages of 400 milligrams to 1,000 milligrams of medroxyprogesterone acetate per week or that 150 milligrams every 3 months can be injected for contraception.


The FDA hasn't approved hydrazine yet. It is used in Russia to fight cancer and is available without a prescription. The full name is Hydrazine Sulfate. If you can't find it, don't worry. I posted my request in other areas so I'm sure I'll get a response either way.

That is about what I had guessed (experimental or folk medicine) since I couldn't find the drug listed in drug references and Bovril and Marmite (see next questions) were only available in England. I do understand your mom's need to find something that works.

Your mom needs to find out about side effects of non-approved medicines or their interference with other prescribed medications. I would suggest she discuss this with her doctor as drugs can interfere with each other's effectiveness.


My mom just started taking hydrazine sulfate today for her cancer. It says not to eat anything with Bovril or Marmite as they will counteract the medicine and make it useless. It is extremely URGENT that I find out what foods contain these two ingredients and what exactly they are.

Also, do you know if they go by any other names so I can look for them in the ingredients on food labels? Thanks so much!!

Bovril and Marmite are the trade names of food products sold mainly in the United Kingdom. I don't know if they are ingredients in any other foods so you will have to read food labels. These products are available in grocery stores in England, Australia, New Zealand, Canada, Hong Kong, Singapore, South Africa and most European countries.

Bovril is a flavoring used in soups or in hot water as a beverage called beef tea or chicken tea depending on the flavor. Due to scares in England about mad cow disease, the manufacturing company removed beef from the product until exporting of beef products resumed. The beef in Bovril currently comes from Sweden and Ireland.

Marmite contains a yeast byproduct from brewing beer, vegetable extract and salt (1 teaspoon has 200 milligrams sodium) that is also used as a spread on toast, flavoring or dissolved in hot water and drank as a beverage. Marmite is a good source of protein (1.5 grams), thiamin (18% RDA), niacin (17% RDA), riboflavin (36% RDA), folic acid (50% RDA) and vitamin B12 (60% RDA).

Hydrazine sulfate was not listed in any of the drug nutrient references I have or the National Institute of Health's Office of Dietary Supplements. I checked the National Cancer Institute and hydrazine sulfate does not shrink tumors or make them go away. According to some research, hydrazine sulfate may be helpful with loss of appetite, body weight and muscle wasting in patients with cancer.


My Mom is currently on medication that can possibly cause liver damage. I'm trying to cook as fat-free as possible, but I'm not too sure about what kind of foods she should be taking and how they should be prepared. She also loves spicy foods such as Indian. Could you please advise me as to what and how I should be preparing her meals? Thank you very much.

What is your mom's diagnosis that she needs a fat-free eating plan? Is she supposed to limit any particular type of fat (cholesterol, saturated fat, trans fat) or all fats? What medication is she taking? Does your mother have high cholesterol or gallbladder disease? Which low fat eating plan she needs will depend on her diagnosis and medications? Has she seen a registered dietitian for nutrition therapy?

Until your mom sees a dietitian, cook without any type of butter, margarine, mayonnaise, salad dressing, lard or oil. Your mom should not add any of these to food before she eats it either. Bake or broil meat, poultry or fish instead of frying. Poultry should be skinless. She should eat small frequent meals so the amount of fat per meal will be lower. Look for foods that have less than 10 grams fat per serving on the food label.

A healthy eating plan with low fat foods (30% of her daily calories) using the Food Guide Pyramid would be best. See the Food Guide Pyramid topic for the recommended number of servings per day. Choose many different foods from the milk, meat, grain, dairy, fruit and vegetable groups. Whether she can have sweets or desserts depends on her overall health status and they will have to be low fat. Limit fats and oils to just the fat in lean meats, poultry (skinless) and fish until your mom has talked to a dietitian who can read her medical chart.

Any spices should be all right, but that depends on the drug your mom is taking as some spices can interfere. Indian foods that are spicy would be fine as long as they are not high fat. Avoid foods with strong odors, lots of fiber or foods that cause gas such as broccoli, Brussels sprouts, cabbage, cauliflower and dried beans and peas.

Another suggestion would be to eliminate alcohol including liquor, wine and beer. While the liver removes alcohol from the blood, fats from the food you eat accumulates in the liver. This diverts the liver from its important job of processing carbohydrate, fats and storing vitamins.


I'm 26 years old, 5 feet 10 inches tall (medium body frame) and weigh 190 pounds. I'm overweight by 40 pounds. I've tried all types of diet products, fad diets and exercises. I would like to regain my youthful weight of 150 pounds and be happy again. Also, what are the effects of weight gain-taking Depo-Provera (sp.)? Any advice given, is greatly appreciated.

Depo Provera is a progesterone contraceptive that can be injected every three months. It is also used to treat endometriosis which causes heavy painful or irregular bleeding due to the lining of the womb which can grow into other parts of the body. It should not be used for more than 2 years unless no other form of birth control will work for you. Weight gain is common because water retention and bloating are side effects. You may experience decreased absorption of some vitamins in particular calcium which may lead to osteoporosis. You should increase your intake of vitamin D which will aid calcium absorption, vitamin C, folic acid (folacin), magnesium, vitamin B6 (pyridoxine), riboflavin (B2) and zinc.

Your healthy body weight is 129 to 173 pounds. Try reducing calories (500 calories less per day) and fat (30% calories from fat) while adding 60 minutes of exercise per day. Weight bearing exercise like weight lifting will decrease calcium losses from bone, decrease body fat and increase muscle mass.


I take Dipentum for ulcerative colitis. What nutrients are being effected by this drug?

Dipentum is an anti-inflammatory drug prescribed for colitis. I checked with drug-nutrient interaction references and cannot find any negative nutrient problems. You should be taking Dipentum with food to avoid an upset stomach. Avoid any exposure to sunlight as it will increase your skin sensitivity so wear sunscreen, sunglasses and protective clothing.


My boyfriend is taking a pill called Parnate and his doctor gave him a list of foods not to eat. Can't he even have a little Colby cheese or chocolate? Some of his most favorite foods were cut out.

The pill he is on is called a MAO inhibitor (monoamine oxidase) which inhibits a brain enzyme that metabolizes noradrenalin also called norepinephrine (hormone produced by adrenal glands and neurons that carries messages to other nerves and is part of the fight or flight response and affects blood pressure) and serotonin (hormone that regulates mood, appetite, sleep, regulates pain and causes blood vessels to narrow). MAO inhibitors are used in antidepressant, anti-Parkinson and anti-Alzheimer drugs. Newer MAO inhibitors are readily reversible in their action and cause less concern about drug food interactions. Your friend should ask his doctor about some of these newer MAO inhibitors.

The nutrition therapy his doctor probably gave him probably restricts tyramine. The tyramine-free nutrition therapy is necessary because foods high in tyramine combined with Parnate or other MAO inhibitors could cause a sudden constriction of blood vessels with increase in blood pressure which can result in a stroke. He must follow the nutrition therapy strictly while on this medication. Tryptophan (a protein amino acid) supplements are not recommended either.

He should follow his doctor's nutrition therapy prescription. The medication may be used for a limited time and if discontinued, the tyramine nutrition therapy should be used an additional 2 weeks after stopping the MAO inhibitor. Here is a list of foods to avoid.

  Foods High in Tyramine Not Allowed
Breads & Starches Cheese breads, cheese crackers and desserts made with cheese other than cheesecake (cream cheese, cottage cheese and ricotta cheese allowed, fruit cake, mince meat cake or pie
Dairy Cheese and cheese sauces, chocolate milk, yogurt, sour cream
Meat Beef or chicken liver, liver sausage or liverwurst, sausages such as bologna, pepperoni, salami, summer sausage, smoked or dried meats like jerky, smoked, dried or pickled fish like pickled herring or anchovies, caviar, shrimp paste, wild game, meat processed with meat tenderizers, meat extracts, tofu bean curd
Fruits Bananas, red plums, canned figs, raisins, prunes
Vegetables Avocado, fava beans, Italian broad beans, sauerkraut, fermented pickles and olives, miso soup, spinach, tomatoes, tomato juice or sauce, tofu bean curd
Beverages Cocoa, alcoholic beverages including Chianti wine, red wine, port, Riesling, sauterne, sherry, vermouth, beer, ale, stout, non-alcoholic beer, distilled spirits such as bourbon, whiskey, scotch, brandy, gin, vodka, rum, tequila, caffeinated beverages like coffee (decaffeinated allowed), tea (decaffeinated allowed), cola, Mountain Dew, energy drinks
Miscellaneous Chocolate, licorice, brewer's yeast or yeast extract, Marmite, meat tenderizer, MSG, soy sauce, teriyaki sauce, catsup, chili sauce, all aged and fermented foods








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