Table 3.

Interactions Between Alcohol and Various Classes of Medications

Drug Class (Conditions for which they are used)	Generic Name	Brand Name	Availability	Type of Interaction
Analgesics (pain relief)	Aspirin	various	Rx and OTC	Aspirin increases gastric emptying, leading to faster alcohol absorption in the small intestine; may also inhibit gastric ADH. Alcohol enhances acetaminophen metabolism into a toxic product, potentially causing liver damage.
	Acetaminophen	e.g., Tylenol
Antibiotics (microbial infections)	Erythromycin	various	Rx	Erythromycin may increase gastric emptying, leading to faster alcohol absorption in the small intestine. Alcohol increases the risk of isoniazid-related liver disease.
	Isoniazid	Nydrazid, Rifamate, Rifater
Anticonvulsants (seizure disorders)	Phenytoin	Dilantin	Rx	Chronic alcohol consumption induces phenytoin breakdown.
Antihistamines (allergies, colds)	Diphenhydramine	e.g., Benadryl	Rx and OTC	lcohol enhances the effects of these agents on the central nervous system (CNS), such as drowsiness, sedation, and decreased motor skills. The interactions are more pronounced in elderly people. No documented interactions exist with nonsedating antihistamines (i.e., certrizine, hismanal, loratidine).
	Chlorpheniramine Clemastine	various
	Hydroxyzine	Atarax, Vistaril
	Promethazine	Phenergan
	Cyproheptadine	Periactin
Anticoagulants (prevention of blood clots)	Warfarin	Coumadin	Rx	Acute alcohol intake may increase anticoagulation by decreasing warfarin metabolism; chronic alcohol ingestion decreases anticoagulation by increasing warfarin metabolism.
Antidiabetic agents (blood sugar regulation)	Chlorpropamide	Diabinese	Rx	Alcohol consumption by diabetic patients taking these medications increases the risk of lower-than-normal blood sugar levels (i.e., hypoglycemia). Chlorpropamide, glyburide, and tolbutamide can cause disulfiram-like interactions after alcohol ingestion. Metformin may cause increased levels of lactic acid in the blood after alcohol consumption.
	Glipizide	Glucotrol
	Glyburide	DiaBeta, Glynase, Micronase
	Tolbutamide	Orinase
	Metformin	Glucophage
Barbiturates (anesthesia, pain relief)	Phenobarbital	various	Rx	Chronic alcohol intake increases barbiturate metabolism by cytochrome P450. Alcohol enhances the sedative and hypnotic effects on the CNS.
Benzodiazepines (sedative agents)	Alprazolam	Xanax	Rx	Alcohol enhances the effects of these agents on the CNS, such as drowsiness, sedation, and decreased motor skills.
	Chlordiazepoxide	Librium
	Clonazepam	Klonopin
	Clorazepate	Tranxene
	Diazepam	Valium
	Lorazepam	Ativan
	Midazolam	Versed
	Oxazepam	Serax
	Temazepam	Restoril
	Triazolam	Halcion
Histamine H2 receptor antagonists (ulcers, heart burn)	Cimetidine	Tagamet	Rx and OTC	The agents inhibit ADH in the stomach, thereby reducing alcohol first-pass metabolism (see figure 1), as well as increase gastric emptying. As a result, BALs are higher than expected for a given alcohol dose; this effect increases over time.
	Nizatidine	Axid
	Ranitidine	Zantac
Immune modulators (rheumatoid arthritis)	Methotrexate	Rheumatrex	Rx	Immune modulators (i.e., medications that affect immune cell function) are associated with a risk of liver damage, which is increased in combination with alcohol.
Muscle relaxants	Carisoprodol	Soma	Rx	Alcohol consumption enhances impairment of physical abilities (e.g., driving) and increases sedation. Carisoprodol produces an opiate-like high when taken with alcohol; it is metabolized to meprobamate and sometimes abused as a street drug.
	Cyclobenzaprine	Flexeril
NSAIDs (pain relief and inflammation)	Ibuprofen	e.g., Motrin	Rx and OTC	Alcohol consumption increases the associated risk of gastrointestinal bleeding.
	Flurbiprofen	various
	Fenoprofen	Nalfon
	Ketoprofen	Orudis
	Naproxen	Naprosyn
	Diclofenac	Voltaren
Opioids (pain relief)	Codeine	various	Rx	Alcohol enhances the effects of these agents on the CNS, such as drowsiness, sedation, and decreased motor skills.
	Hydromorphone	Dilaudid
	Fentanyl	generic
	Morphine	various
	Meperidine	e.g., Demerol
	Propoxyphene	Darvon, Wygesic
Sedatives and hypnotics	Chloral hydrate	Noctec	Rx	Alcohol inhibits the metabolism of these agents and produces a depressant effect on the CNS that includes sleepiness, disorientation, incoherence, and confusion.
	Meprobamate	Equanil, Miltown
Tricyclic antidepressants (depression)	Amitriptyline	Elavil, Endep	Rx	Alcohol consumption increases the risk of sedation and a sudden drop in blood pressure when a person stands up (i.e., orthostatic hypotension).
	Clomipramine	Anafranil
	Desipramine	Norpramin
	Doxepin	Adapin, Sinequan
	Imipramine	Tofranil
	Nortriptyline	Aventyl, Pamelor
	Trimipramine	Surmontil
Herbal medications (sleep aids)	Chamomile	various	OTC	Alcohol may accentuate the drowsiness that is associated with these herbal preparations.
	Echinacea	preparations
	Valerian

ADH = alcohol dehydrogenase; BAL = blood alcohol level; NSAIDs = nonsteroidal anti-inflammatory drugs; OTC = over the counter; Rx = prescription.