Cialis is the brand name for the medication tadalafil, which is used to treat erectile dysfunction (ED) and symptoms of benign prostatic hyperplasia (BPH). Cialis is a type of phosphodiesterase-5 (PDE5) inhibitor, which means that it works by inhibiting the enzyme PDE5, which breaks down cyclic guanosine monophosphate (cGMP). By inhibiting PDE5, Cialis allows cGMP to accumulate, which relaxes smooth muscle cells in the blood vessels of the penis and increases blood flow, leading to an erection.

Cialis is available in several forms, including tablets, capsules, and a liquid form. It is usually taken before sexual activity and can be taken with or without food. The recommended starting dose is 10 mg, which can be adjusted based on the individual’s response and tolerability. The maximum recommended dose is 20 mg.

Common side effects of Cialis include headache, upset stomach, back pain, muscle aches, flushing, and stuffy or runny nose. More serious side effects are rare but can include a prolonged erection, which can be painful and requires immediate medical attention. Cialis can also interact with certain medications, so it is important to tell your healthcare provider about all the medications you are taking before starting Cialis.

Cialis is a prescription medication and is not available over-the-counter. It is important to only take Cialis as directed by a healthcare provider.