A single drink can inhibit the metabolism of a drug in the liver, which prolongs and increases the effect of the drug, and its side effects. In alcoholics, the opposite process may occur, i.e. faster drug metabolism and less efficacy. The alcoholic may need higher doses of medication.

Alcohol can also convert some drugs into toxins, which can, for example, damage the liver, kidneys, etc. Antibiotics combined with a single dose of alcohol can cause nausea, vomiting, headaches, convulsions, e.g. metronidazole.

A lot of people use anticoagulants. Alcohol can exacerbate the effects of the drug, increasing the risk of haemorrhage. Chronic drinking can have the opposite effect.

Alcoholics often suffer from depression. Note that alcohol increases the sedative effect of tricyclic antidepressants (amitriptyline) Some wine/drinking used together with monoamine oxidase inhibitors (antidepressants), may result in a large increase in blood pressure. Popular over-the-counter antihistamines, e.g. diphenhydramine, used for allergies, insomnia, together with alcohol can have a stronger sedative effect and cause dizziness.Common anti-ulcer drugs, e.g. ranitidine (ranigast), can increase the effect of already low doses of alcohol.

Many people suffer from hypertension. Alcohol can both increase (e.g. methyldopa, hydralazine) the blood pressure lowering effect or decrease e.g. in the case of some beta blockers (propranolol). Alcohol used together with drugs increases the risk of toxic effects and death. When aspirin is combined, alcohol can cause gastric bleeding. In addition, aspirin can increase the intoxicating effects and alcohol. It is toxic to the liver to combine paracetamol with alcohol.

Read the leaflets carefully. If you are unsure about the effects of combining a single drink with medication, seek advice from your pharmacist or doctor.