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Can food and drugs cause severe side effects when taken together?


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.

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. Not only can drugs interact with food and alcohol, they can also interact with each other. Some drugs are given together on purpose for an added effect, like codeine and acetaminophen for pain relief. But other drug-to-drug interactions may be unintended and harmful. Prescription drugs can interact with each other or with over-the-counter (OTC) drugs, such as acetaminophen, aspirin, and cold medicine. Likewise, OTC drugs can interact with each other. 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.


Last Reviewed: 04/23/2008