&
Drug
Interactions
|
Food & Drug Interactions |
Medicines can treat and cure many health
problems. However, they must be taken
properly to ensure that they are safe and
effective. Many medicines have powerful
ingredients that interact with the human body
in different ways, and diet and lifestyle can
sometimes have a significant impact on a drug's
ability to work in the body. Certain foods,
beverages, alcohol, caffeine, and even cigarettes
can interact with medicines. This may make
them less effective or may cause dangerous side
effects or other problems.
When you take medicine, be sure to follow your doctor's instructions carefully to obtain the maximum benefit with the least risk. Changes in a medicine's effect due to an interaction with food, alcohol or caffeine can be significant; however, there are many individual factors that influence the potential for such variations, like dose, age, weight, sex, and overall health.
This brochure has information about possible interactions between many common prescription and nonprescription (over-the- counter) medications with food, alcohol and caffeine. But this brochure should not replace the advice from your physician, pharmacist, or other health care professional. If you have any questions or concerns about possible drug interactions, consult your health care professional.
Make sure your doctor and pharmacist know about every drug you are taking, including nonprescription drugs and any dietary supplements such as vitamins, minerals and herbals. If you have problems or experience side effects related to medication, call your health care provider right away. It is also important to remember that many drugs interact with other drugs and may cause serious medical conditions.
In this brochure, the generic (nonproprietary)
name for each drug is stated first. Brand names
are in full capital letters and represent only some
examples of those medications.
ALLERGIES |
Antihistamines are used to relieve or prevent the symptoms of colds, hay fever, and allergies. They limit or block histamine, which is released by the body when we are exposed to substances that cause allergic reactions. Antihistamines are available with and without a prescription (over- the-counter). These products vary in their ability to cause drowsiness and sleepiness.
Alcohol: Some antihistamines may increase drowsiness and slow mental and motor performance. Use caution when operating machinery or driving.
ARTHRITIS AND PAIN |
Interactions
Food: For rapid relief, take on an
empty stomach because food may slow the
body's absorption of acetaminophen.
Alcohol: Avoid or limit the use of alcohol because chronic alcohol use can increase your risk of liver damage or stomach bleeding. If you consume three or more alcoholic drinks per day talk to your doctor or pharmacist before taking these medications.
Interaction
Food: Because these medications can irritate the
stomach, it is best to take them with food or milk.
Alcohol: Avoid or limit the use of alcohol because chronic alcohol use can increase your risk of liver damage or stomach bleeding. If you consume three or more alcoholic drinks per day talk to your doctor or pharmacist before taking these medications. Buffered aspirin or enteric coated aspirin may be preferable to regular aspirin to decrease stomach bleeding.
Interaction
Food: Take with food or milk to decrease stomach
upset.
NARCOTIC ANALGESICS
Narcotic analgesics are available only with a
prescription. They provide relief for moderate
to severe pain. Codeine can also be used to
suppress cough. Some of these medications can
be found in combination with non-narcotic drugs
such as acetaminophen, aspirin, or cough syrups.
Use caution when taking these medications: take
them only as directed by a doctor or pharmacist
because they may be habit forming and can cause
serious side effects when used improperly.
Interaction
Alcohol: Avoid alcohol because it increases the
sedative effects of the medications. Use caution
when motor skills are required, including
operating machinery and driving.
ASTHMA |
Interactions
Food: The effect of food on theophylline
medications can vary widely. High-fat meals
may increase the amount of theophylline in the
body, while high-carbohydrate meals may
decrease it. It is important to check with your
pharmacist about which form you are taking
because food can have different effects
depending on the dose form (e.g., regular release,
sustained release or sprinkles) For example, food
has little effect on Theo-Dur and Slo-Bid, but
food increases the absorption of Theo-24 and
Uniphyl which can result in side effects of
nausea, vomiting, headache and irritability.
Food can also decrease absorption of products
like Theo-Dur Sprinkles for children.
Caffeine: Avoid eating or drinking large amounts of foods and beverages that contain caffeine (e.g., chocolate, colas, coffee, tea) because both oral bronchodilators and caffeine stimulate the central nervous system.
Alcohol: Avoid alcohol if you're taking theophylline medications because it can increase the risk of side effects such as nausea, vomiting, headache and irritability.
CARDIOVASCULAR DISORDERS |
Interaction
Food: Diuretics vary in their interactions with
food and specific nutrients. Some diuretics cause
loss of potassium, calcium, and magnesium.
Triamterene, on the other hand, is known as a
"potassium-sparing" diuretic. It blocks the
kidneys’ excretion of potassium, which can cause
hyperkalemia (increased potassium). Excess
potassium may result in irregular heartbeat and
heart palpitations. When taking triamterene,
avoid eating large amounts of potassium-rich
foods such as bananas, oranges and green leafy
vegetables, or salt substitutes that contain
potassium.
Interaction
Alcohol: Avoid alcohol because it may add to
the blood vessel-relaxing effect of nitrates and
result in dangerously low blood pressure.
Interactions
Food: Food can decrease the absorption of
captopril and moexipril. So take captopril and
moexipril one hour before or two hours after
meals. ACE inhibitors may increase the amount
of potassium in your body. Too much potassium
can be harmful. Make sure to tell your doctor if
you are taking potassium supplements or
diuretics (water pills) that may increase the
amount of potassium in your body. Avoid eating
large amounts of foods high in potassium such
as bananas, green-leafy vegetables, and oranges.
Food: Lovastatin (Mevacor) should be taken with the evening meal to enhance absorption.
Interactions
Food: Vitamin K produces blood-clotting
substances and may reduce the effectiveness of
anticoagulants. So limit the amount of foods
high in vitamin K (such as broccoli, spinach, kale,
turnip greens, cauliflower, and brussel sprouts).
High doses of vitamin E (400 IU or more ) may prolong clotting time and increase the risk of bleeding. Talk to your doctor before taking vitamin E supplements.
INFECTIONS |
Interaction
Food: Take on an empty stomach, but if it upsets
your stomach, take it with food.
Interactions
Food: Take on an empty stomach one hour
before or two hours after meals. If your stomach
gets upset, take it with food. However, avoid
calcium-containing products like milk, yogurt,
vitamins or minerals containing iron, and
antacids because they significantly decrease
drug concentration.
Caffeine: Taking these medications with caffeine- containing products (e.g., coffee, colas, tea, and chocolate) may increase caffeine levels, leading to excitability and nervousness.
Interaction
Food: Take on an empty stomach one hour
before or two hours after meals. If your stomach
gets upset, take with food.
Interaction
Food: Take on an empty stomach one hour
before or two hours after meals. If your stomach
gets upset, take with food.
Interaction
Food: Take on an empty stomach one hour
before or two hours after meals. If your stomach
gets upset, take with food.
Interaction
Food: Take on an empty stomach one hour
before or two hours after meals. If your stomach
gets upset, take with food. However, it is
important to avoid taking tetracycline /
ACHROMYCIN, SUMYCIN with dairy
products, antacids and vitamins containing iron
because these can interfere with the medication's
effectiveness.
Interaction
Alcohol: Avoid drinking alcohol or using
medications that contain alcohol or eating foods
prepared with alcohol while you are taking
metronidazole and for at least three days after
you finish the medication. Alcohol may cause
nausea, abdominal cramps, vomiting,
headaches, and flushing.
Interaction
Food: It is important to avoid taking these
medications with dairy products (milk, cheeses,
yogurt, ice cream), or antacids.
Alcohol: Avoid drinking alcohol, using medications that contain alcohol, or eating foods prepared with alcohol while you are taking ketoconazole/NIZORAL and for at least three days after you finish the medication. Alcohol may cause nausea, abdominal cramps, vomiting, headaches and flushing.
MOOD DISORDERS |
Interactions
MAO Inhibitors have many dietary restrictions,
and people taking them need to follow the
dietary guidelines and physician's instructions
very carefully. A rapid, potentially fatal increase
in blood pressure can occur if foods or alcoholic
beverages containing tyramine are consumed
while taking MAO Inhibitors.
Alcohol: Do not drink beer, red wine, other alcoholic beverages, non-alcoholic and reduced alcohol-beer and red-wine products.
Food: Foods high in tyramine that should be avoided include:
Interaction
Alcohol: May impair mental and motor
performance (e.g., driving, operating
machinery).
Caffeine: May cause excitability, nervousness, and hyperactivity and lessen the anti-anxiety effects of the drugs.
Interactions
Alcohol: Although alcohol may not significantly
interact with these drugs to affect mental or
motor skills, people who are depressed should
not drink alcohol.
Food: These medications can be taken with or without food.
STOMACH CONDITIONS |
Conditions like acid reflux, heartburn, acid indigestion, sour stomach, and gas are very common ailments. The goal of treatment is to relieve pain, promote healing and prevent the irritation from returning. This is achieved by either reducing the acid the body creates or protecting the stomach from the acid. Lifestyle and dietary habits can play a large role in the symptoms of these conditions. For example, smoking cigarettes and consuming products that contain caffeine may make symptoms return.
Interactions
Alcohol: Avoid alcohol while taking these
products. Alcohol may irritate the stomach and
make it more difficult for the stomach to heal.
Food: Can be taken with or without regard to meals.
Caffeine: Caffeine products (e.g., cola, chocolate, tea and coffee) may irritate the stomach.
DRUG-TO-DRUG INTERACTIONS |
Sometimes the effect of one drug may be increased or decreased. For example, tricyclic antidepressants such as amitriptyline (ELAVIL), or nortriptyline (PAMELOR) can decrease the ability of clonidine (CATAPRES) to lower blood pressure. In other cases, the effects of a drug can increase the risk of serious side effects. For example, some antifungal medications such as itraconazole (SPORANOX) and ketoconazole (NIZORAL) can interfere with the way some cholesterol-lowering medications are broken down by the body. This can increase the risk of a serious side effect.
Doctors can often prescribe other medications to reduce the risk of drug-drug interactions. For example, two cholesterol- lowering drugs — pravastatin (PRAVACHOL) and fluvastatin (LESCOL), are less likely to interact with antifungal medications. Be sure to tell your doctor about all medications — prescription and OTC— that you are taking.
This brochure was produced in 1998 as a joint venture between the U.S. Food and Drug Administration (FDA, www.fda.gov) and the National Consumers League (www.nclnet.org).