Updated May 08, 2015.

Written or reviewed by a board-certified physician. See About.com's Medical Review Board.

If you are taking medication, even some over-the-counter medications or herbal remedies, drinking alcohol can have serious consequences. Mixing alcohol with some medications can make them less effective, cause harmful side effects or make them toxic to your system.

If your medication's packaging contains a warning against mixing it with alcohol, that warning is there for a reason. Mixing alcohol with some medications -- even hours after taking the medication -- can cause a wide range of reactions, including nausea and vomiting, headaches, drowsiness, fainting, or loss of coordination.

Mixing alcohol with some medications increase the risk for internal bleeding, heart problems, and difficulties in breathing.

More Than One Danger

Many medications contain more than one ingredient, and all of them can interact with alcohol differently. Some medications contain alcohol themselves, which can increase your blood-alcohol level if you are also drinking.

Drinking alcohol itself can make driving a vehicle or operating machinery more dangerous. Mixing alcohol with certain medications can put you at even greater risk. Research has shown that mixing alcohol with medications is even more dangerous for women and older people.

Medications That React With Alcohol

Following is a list of some kinds of medications that can interact with alcohol, the type of reactions they can cause and their brand names. This is by no means a complete list of all medications that can react with alcohol; these are some of the more popular medications.

The links below will take you to an expanded description of each drug, its side effects, uses and other possible interactions.

Allergy, Cold and Flu Medications

Possible Reactions: Drowsiness, dizziness; increased risk for overdose.

Brand Names: Alavert, Allegra, Allegra-D, Benadryl, Clarinex, Claritin, Claritin-D, Dimetapp Cold & Allergy, Sudafed Sinus & Allergy, Triaminic Cold & Allergy, Tylenol Cold & Flu and Zyrtec.

Chest Pain, Coronary Heart Disease Medication

Possible Reactions: Rapid heartbeat, sudden changes in blood pressure, dizziness, fainting.

Brand Names: Isordil (nitroglycerin).

Anxiety and Epilepsy Medications

Possible Reactions: Drowsiness, dizziness; increased risk for overdose; slowed or difficulty breathing; impaired motor control; unusual behavior; liver damage and memory problems.

Brand Names: Ativan, Klonopin, Paxil, Valium, Xanax and herbal preparations (Kava Kava).

Arthritis Medications

Possible Reactions: Ulcers, stomach bleeding, liver problems.

Brand Names: Celebrex, Naprosyn, and Voltaren.

Blood Clot Medication

Possible Reactions: Occasional drinking may lead to internal bleeding; heavier drinking also may cause bleeding or may have the opposite effect, resulting in possible blood clots, strokes, or heart attacks.

Brand Names: Coumadin (warfarin).

Cough Medications

Possible Reactions: Drowsiness, dizziness; increased risk for overdose.

Brand Names: Robitussin A–C, Delsym, Robitussin Cough.

Depression Medications

Possible Reactions: Drowsiness, dizziness; increased risk for overdose; increased feelings of depression or hopelessness in adolescents (suicide).

Brand Names: Anafranil, Celexa, Effexor, Elavil, Lexapro, Luvox, Norpramin, Paxil, Serzone, Wellbutrin, Zoloft and herbal preparations (St. John’s Wort).

Diabetes Medications

Possible Reactions: Abnormally low blood sugar levels, flushing reaction (nausea, vomiting, headache, rapid heartbeat, sudden changes in blood pressure).

Brand Names: Glucophage, Micronase, and Orinase.

Enlarged Prostate Medications

Possible Reactions: Dizziness, light headedness, fainting.

Brand Names: Cardura, Flomax, and Minipress.

Heartburn and Indigestion Medications

Possible Reactions: Rapid heartbeat, sudden changes in blood pressure (Reglan); increased alcohol effect.

Brand Names: Axid, Reglan, Tagamet and Zantac.

High Blood Pressure Medications

Possible Reactions: Dizziness, fainting, drowsiness; heart problems such as changes in the heart’s regular heartbeat (arrhythmia).

Brand Names: Accupril, Capozide, Cardura, Catapres, Cozaar, Hytrin, Lopressor HCT, Lotensin, Minipress and Vaseretic.

High Cholesterol Medications

Possible Reactions: Liver damage; increased flushing and itching, increased stomach bleeding.

Brand Names: Advicor, Altocor, Crestor, Lipitor, Mevacor, Niaspan, Vytorin and Zocor.

Infection Medications

Possible Reactions: Fast heartbeat, sudden changes in blood pressure; stomach pain, upset stomach, vomiting, headache, or flushing or redness of the face; liver damage.

Brand Names: Flagyl, Nizoral, Nydrazid, Tindamax.

Muscle Pain Medications

Possible Reactions: Drowsiness, dizziness; increased risk of seizures; increased risk for overdose; slowed or difficulty breathing; impaired motor control; unusual behavior; memory problems.

Brand Names: Flexeril, Soma, Antivert, and Atarax.

Nausea and Motion Sickness Medications

Possible Reactions: Drowsiness, dizziness; increased risk for overdose.

Brand Names: Antivert, Atarax, Dramamine and Phenergan.

Pain, Fever and Inflammation

Possible Reactions: Stomach upset, bleeding and ulcers; liver damage; rapid heartbeat.

Brand Names: Advil, Aleve, Excedrin, Motrin, and Tylenol.

Seizure Medications

Possible Reactions: Drowsiness, dizziness; increased risk of seizures.

Brand Names: Dilantin and Klonopin.

Severe Pain Medications

Possible Reactions: Drowsiness, dizziness; increased risk for overdose; slowed or difficulty breathing; impaired motor control; unusual behavior; memory problems.

Brand Names: Darvocet–N, Demerol, Fiorinal, Percocet and Vicodin.

Sleep Medications

Possible Reactions: Drowsiness, sleepiness, dizziness; slowed or difficulty breathing; impaired motor control; unusual behavior; memory problems.

Brand Names: Ambien, Lunesta, Prosom, Restoril, Unisom and herbal preparations (chamomile, valerian, lavender).

<sub>Source:

National Institute on Alcohol Abuse and Alcoholism "Harmful Interactions: Mixing Alcohol and Medications." Revised 2007</sub>