Tadalafil: What It Does and How to Use It

Thinking about tadalafil? It’s a popular medicine for erectile dysfunction (ED) and a prescription option for pulmonary arterial hypertension (PAH). It works by relaxing blood vessels so blood flows better. That simple action helps erections and can lower pressure in the lungs when used for PAH.

How to take tadalafil

There are two common ways people use tadalafil: as-needed and daily. For ED, as-needed doses typically range from 5–20 mg taken about 30–60 minutes before sex. It can last up to 36 hours, which is why people call it the "weekend pill." For daily use, low doses like 2.5–5 mg once a day let you be ready anytime. For PAH, doctors usually prescribe a once-daily dose (follow your provider's instructions; brands and dosing differ).

Food: you can take tadalafil with or without food. A heavy, high-fat meal may slow how fast it works, though it won’t stop it. Alcohol in small amounts is usually fine, but heavy drinking can raise the chance of dizziness or low blood pressure.

Safety, side effects, and interactions

Common side effects are headache, flushing, indigestion, back pain, and stuffy nose. These often pass within a few hours. Serious problems are rare but need urgent care: if an erection lasts more than 4 hours (priapism), or you experience sudden vision or hearing loss, seek emergency help immediately.

Don’t take tadalafil with any nitrate medication (nitroglycerin, isosorbide) — that combo can cause a dangerous drop in blood pressure. Be cautious if you’re on alpha-blockers for prostate issues or blood pressure; your doctor will advise timing or dose changes. Strong CYP3A4 inhibitors (like ritonavir, ketoconazole) can raise tadalafil levels — your doctor may lower the dose. Grapefruit and grapefruit juice can also increase drug levels, so avoid large amounts.

If you have severe liver or kidney problems, or certain heart conditions, your doctor may change the dose or recommend a different treatment. Older adults usually start at lower doses to reduce side effects.

Buying online? Always use a licensed pharmacy that asks for a prescription. Watch for prices that are too low, no contact info, or medicines without proper packaging — these can be counterfeit. If you’re uncertain, ask your healthcare provider or check pharmacy reviews and credentials.

Storage is simple: keep tadalafil at room temperature away from moisture and heat. Keep it out of reach of children and pets.

Want a quick checklist before you take tadalafil? Make sure a doctor approved it, tell them about all meds and health conditions, avoid nitrates, watch for severe side effects, and buy from a reputable source. That covers the essentials and helps you use tadalafil safely and effectively.