Tadarise 2.5 mg contains tadalafil, a PDE5 inhibitor. Alcohol is limited because both alcohol and tadalafil can widen blood vessels and lower blood pressure. Taking them together—especially with substantial alcohol—can make the blood-pressure drop stronger. D DailyMed +1 This can cause: Dizziness or light-headedness, particularly when standing Headache and flushing Faster heartbeat In some cases, fainting due to low blood pressure D DailyMed The prescribing information specifically warns about substantial alcohol consumption (around 5 or more units) with tadalafil. A small amount may be tolerated by many people, but individual responses vary. D DailyMed Also, never combine tadalafil with nitrate medicines such as nitroglycerin/GTN or isosorbide, regardless of the amount of alcohol involved. This combination can cause a dangerous fall in blood pressure. D DailyMed