Cialis is a medicine used to treat erectile dysfunction (ED) and, in some cases, benign prostatic hyperplasia (BPH). It works by relaxing blood vessels in the penis, increasing blood flow and helping to achieve and maintain an erection during sexual stimulation. Cialis is the active ingredient in the brand Cialis.

Cialis is effective in around 8 out of 10 men with erectile dysfunction. Clinical studies show strong improvement in erection quality, often regardless of the underlying cause of ED. It works best when taken correctly and combined with healthy lifestyle choices such as limiting alcohol and stopping smoking.

Cialis is often called the “weekend pill” because it can last up to 36 hours. You may still respond to sexual stimulation at any time during this window. The duration is much longer than sildenafil (Viagra), which usually lasts 4–6 hours.

Take Cialis with a glass of water. It can be taken with or without food. For on-demand use, take it at least 30 minutes before planned sexual activity. Do not take more than one dose in 24 hours. There is also a lower daily dose option that allows for more spontaneous activity.

Cialis comes in 2.5 mg, 5 mg, 10 mg and 20 mg tablets. The usual starting dose is 10 mg when needed, before sexual activity. Depending on your response, your doctor may adjust to 20 mg or reduce to 5 mg. For daily use, the dose is normally 2.5 mg or 5 mg once daily. Always follow your prescriber’s instructions.

Common side effects include headache, indigestion, flushing, nasal congestion, back pain and muscle aches. These usually improve after a few hours. Less common but serious risks include chest pain, sudden loss of vision or a prolonged painful erection lasting more than 4 hours. Seek urgent medical help if these occur.

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There is no medical difference. Cialis is the original brand name, while tadalafil is the generic version. Both contain the same active ingredient and work in the same way. The main difference is cost, as generic tadalafil is usually more affordable than branded Cialis.