Tadalis SX 20 mg is not generally considered safe for daily use unless specifically prescribed by a doctor, because 20 mg is a higher “as‑needed” dose of tadalafil and repeated daily intake can raise the risk of side effects and interactions. How Tadalis SX 20 mg is usually used Tadalis SX 20 mg is designed as an “on‑demand” erectile‑dysfunction medicine, taken about 30 minutes to 1 hour before sex, up to once per day, not as a routine daily tablet. Daily tadalafil regimens almost always use lower doses (such as 2.5–5 mg), not 20 mg, to reduce blood‑pressure drops, dizziness, headache, and other side effects. When daily 20 mg is risky Avoid daily use if you have heart disease, low blood pressure, recent stroke or heart attack, severe liver disease, or if you take nitrates (for chest pain) or certain blood‑pressure or prostate medicines, because tadalafil can worsen these conditions. Alcohol, grapefruit products, and some antibiotics or antifungals can also increase side‑effect risk when combined with tadalafil.