Patient Safety: Dangerous Drug Interactions

Almost every time you visit the doctor, one of the first questions your doctor will ask you is, "Are you taking any medications?" It is important for you to be prepared to answer with a complete list of all prescription medications, herbal remedies, non-prescription medicines, vitamins, minerals and dietary supplements that you may be using. While individually each medication is designed to make you feel better, if two or more medications are taken at the same time, it is possible the drugs will interact in a way that is harmful to your body.

Drug interactions may make your drug less effective, cause unexpected side effects, or increase or lessen the action of a particular drug. Some drug interactions can be very harmful to you. There are four main types of drug interactions:

1. Taking drugs with other drugs
This includes both prescription and over-the-counter medicines. For example, certain antidepressants can interfere with blood pressure-lowering drugs. Some antibiotics can lower the effectiveness of birth control pills.

2. Taking drugs with food and beverages
Drinks such as colas, coffee, and chocolate that contain caffeine may cause excitability and nervousness when taking certain drugs. Grapefruit juice should not be taken with certain blood pressure-lowering drugs. Alcohol interacts with almost every medication, especially antidepressants and other drugs that affect the brain and nervous system.

3. Taking drugs with dietary supplements
This includes herbs and vitamins, which can interact with drug-metabolizing enzymes. For example, ginseng can increase blood pressure, and when taken with the blood-thinning drug Coumadin, this interaction can cause bleeding episodes.

4. Taking drugs with a medical condition
An existing medical condition can make certain drugs potentially harmful. For example, if you have high blood pressure you could experience an unwanted reaction if you take a nasal decongestant.

Medication taken orally travels through the digestive system in the same way as anything you eat or drink. So when a drug is mixed with another drug, food or a dietary supplement, each can alter the way the body metabolizes, or processes, the other.

Patients at high risk for drug interactions include:

• The elderly
• Anyone taking three or more medications for chronic conditions
• Patients suffering from diabetes, hypertension, depression, high cholesterol or congestive heart failure

How can you avoid drug interactions?

• Talk with your doctor or pharmacist before taking any new medication, prescription or over-the-counter, and ask whether it is safe to take the new medicine with other over-the-counter medicines, prescription medications, vitamins or herbal products you are already taking
• Thoroughly read the labels of all over-the-counter and prescription medicines -- pay close attention to dosage instructions, potential side effects, and any other warnings
• Keep a record listing your over-the-counter and prescription drugs, and take it with you when you visit your doctor or pharmacist
• Use one pharmacy for all of your medication purchases