Fildena CT 100 mg works by inhibiting the PDE5 enzyme, which normally breaks down cyclic GMP (cGMP). cGMP relaxes the smooth muscles in the penile blood vessels, allowing them to widen and fill with blood during sexual stimulation. The erection occurs only with sexual arousal, so the drug does not cause spontaneous erections. Common side effects include headache, flushing, dizziness, nasal congestion, and upset stomach. Rare but serious side effects can include prolonged erection (priapism), sudden vision or hearing loss, or chest pain.
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