Alcohol is a drug that depresses the central nervous system. Like any drug, alcohol can interact with a wide variety of compounds. Many medications can alter the metabolism (breakdown) or effects of alcohol, and vice versa. Some of these interactions can occur even at moderate drinking levels and result in side effects for the drinker.
Two types of alcohol-medication interactions exist: interactions where alcohol interferes with the metabolism of the medication in the liver, and interactions where alcohol enhances the effects of the medication, particularly in the central nervous system (e.g., sedation). Numerous types of medications (prescription and over-the-counter) can interact with alcohol, including antibiotics, antidepressants, antihistamines, barbiturates, benzodiazepines, histamine H2 receptor antagonists, muscle relaxants, non-narcotic pain medications and anti-inflammatory agents, opioids, and blood thinners.
All antidepressants cause various levels of sedation and interact with alcohol in the following ways:
- Tricyclic antidepressants cause the most sedation. Alcohol increases these effects and can cause increased drug levels in the body. High TCA levels, in turn, can lead to convulsions and disturbances in heart rhythm.
- SSRIs are much less sedating than the TCAs and have the best safety profile of all the antidepressants. No significant interactions appear to occur when these agents are combined with moderate amounts of alcohol.
- People taking MAO inhibitors can experience major side effects when combined with alcohol. MAO inhibitors can cause dangerously high blood pressure if consumed together with tyramine, found in beer and red wine.
- Atypical antidepressants may cause enhanced sedation when combined with alcohol.
Alcohol use while taking antidepressants is discouraged by all manufacturers of the drugs. In addition, alcohol is known to cause or worsen depression and should generally be avoided while on antidepressants. The recurrent use of even small amounts of alcohol (e.g. one drink per day) has been shown to reduce the potential for full benefits of antidepressants. If you choose to drink alcohol while taking antidepressants, you should use extreme caution.
Although many people drink alcohol while on medications, most studies assessing interactions focus on the effects of chronic heavy drinking. Little is known about medication interactions resulting from moderate alcohol consumption (i.e., one or two drinks per day).
By and large, alcohol and drugs don't mix. And given the complexity of the interactions between alcohol and numerous medications, it is difficult to recommend a level of alcohol consumption that can be considered safe when taking antidepressants.