Tadalafil (Cialis): What it does and how to use it

Tadalafil is a medicine most people know as Cialis. It treats erectile dysfunction (ED), helps lower urinary symptoms from an enlarged prostate (BPH), and in a different brand it treats pulmonary arterial hypertension. The big selling point is how long it works: effects can last up to 36 hours, so timing is more forgiving than with other ED pills.

How tadalafil works and common doses

Tadalafil relaxes blood vessels by blocking the enzyme PDE5. That increases blood flow to the penis during sexual arousal and eases bladder symptoms in BPH. For ED you’ll usually see these options: as-needed dosing (5–20 mg taken before sex) or daily low-dose (2.5–5 mg once daily). For BPH and combined BPH/ED, doctors often prefer daily dosing. For pulmonary hypertension a higher daily dose is used under specialist care (follow your prescriber's instructions).

Expect onset around 30–60 minutes for many people, though some feel it sooner and others later. Because it can last up to 36 hours, you don’t need to rush: a single dose can cover a whole weekend night.

Safety tips, side effects, and interactions

Common side effects are headache, flushing, indigestion, back pain, muscle aches, nasal congestion and dizziness. These usually fade in a day or two. Serious issues are rare but important: sudden vision loss, sudden hearing loss, and priapism (a painful erection lasting more than four hours). If any of those happen, get emergency care.

Do not take tadalafil with nitrates (nitroglycerin or similar) — together they can cause a dangerous drop in blood pressure. Be cautious if you take alpha-blockers, some blood pressure meds, or strong CYP3A4 inhibitors (like certain antifungals and HIV drugs). If you have heart disease, uncontrolled high blood pressure, severe liver or kidney problems, talk to your doctor before using tadalafil. Avoid large amounts of grapefruit juice; it can raise tadalafil levels.

Dosage may need adjustment for older adults or those with kidney or liver issues. If you miss a daily dose, take it when you remember unless it’s near the next dose. Don’t double up.

Want practical tips? Start with the lowest effective dose your doctor suggests. Try the as-needed option first to see how your body reacts. If you need frequent treatment or notice BPH symptoms improving, ask about daily dosing.

Thinking about buying tadalafil online? Use a licensed pharmacy, require a prescription, read real reviews, check the site’s contact details and secure checkout (https/SSL). If a price looks too good to be true or the site skips prescriptions, walk away.

Questions about interactions with other meds or how to switch from another ED drug? Ask your clinician — they can match dosing to your heart, liver and kidney status. Tadalafil is powerful and convenient when used the right way.