Cialis (tadalafil): What it does and why people choose it

Did you know Cialis can work for up to 36 hours? That long window is why many men pick it. Cialis is the brand name for tadalafil, a medicine that helps blood flow to the penis by blocking an enzyme called PDE5. That makes getting and keeping an erection easier when you’re sexually aroused.

Cialis comes in two main ways: on-demand (10–20 mg) and daily low-dose (2.5–5 mg). On-demand means you take a pill before sex; daily dosing keeps a steady level in your body so you don’t have to time it. Which one fits you depends on how often you want sex and what your doctor recommends.

How to use Cialis safely

For on-demand use, take Cialis about 30–60 minutes before sex. It may work faster or slower depending on you. Don’t take more than one dose a day. For daily use, take the same low dose at roughly the same time every day, with or without food.

Common doses: 2.5 mg and 5 mg for daily use; 10 mg and 20 mg for on-demand. Doctors usually start with a middle dose and adjust based on effect and side effects.

Side effects, warnings, and interactions

Most side effects are mild: headache, flushing, upset stomach, back pain, or muscle aches. These usually fade in a day or two. Stop the drug and get urgent care if you have an erection lasting more than four hours (priapism) or sudden vision or hearing loss.

Never take Cialis with nitrates (often prescribed for chest pain). That combo can drop blood pressure dangerously. Also be careful if you take alpha-blockers, certain blood pressure meds, or strong CYP3A4 inhibitors like some antifungals or HIV drugs—these can change tadalafil levels.

Alcohol can blunt performance and increase dizziness. Moderate drinking is usually okay, but heavy drinking raises risks.

If you have heart disease, recent stroke, or uncontrolled blood pressure, talk to your doctor before use. Your doctor will weigh risks versus benefit and may suggest testing or a safer option.

Buying tip: get a prescription and use a reputable pharmacy. Fake ED pills are common online and can be dangerous. Check seals, batch numbers, and pharmacy reviews. GlobalPharmacyPlus has guides on safe online pharmacies and how to spot fakes.

Alternatives: sildenafil (Viagra) works faster but wears off sooner. Vardenafil (Levitra) and avanafil (Stendra) are other prescription options with slightly different timing and side-effect profiles. Non-drug routes—exercise, weight loss, quitting smoking, therapy, vacuum devices, or penile injections—can help too, depending on the cause.

Want to learn more? Read trusted reviews, compare on-demand vs daily use, and ask your doctor about interactions with your current meds. Practical choices and honest discussion with a clinician make the biggest difference.