Alcohol consumption can have harmful effects on the efficacy of medications. According to DrugPatentWatch , alcohol can interact with various drugs, potentially altering their effectiveness. The site lists several medications that should not be taken with alcohol, including antibiotics, anticoagulants, and antidepressants. Alcohol can also increase the risk of side effects from medications, such as drowsiness, dizziness, and impaired coordination.
The National Institute on Alcohol Abuse and Alcoholism  also warns of the dangers of mixing alcohol with medications. The institute states that alcohol can interact with over-the-counter and prescription medications, including pain relievers, sleeping pills, and allergy medications. These interactions can cause serious health problems, including liver damage, heart problems, and internal bleeding.
A study published in the Journal of Clinical Medicine Research  found that alcohol consumption can affect the pharmacokinetics of medications, which can alter their efficacy. The study suggests that alcohol can affect the absorption, distribution, metabolism, and excretion of medications, potentially leading to changes in their therapeutic effects.
In conclusion, alcohol consumption can have harmful effects on medication efficacy. It is important to consult with a healthcare provider before consuming alcohol while taking any medication. Patients should also read the labels of their medications to determine if alcohol consumption is contraindicated.