Valif 20 mg is typically taken about 30–60 minutes before sexual activity, with or without food, though heavy meals may delay the onset of action. The effects can last for several hours, giving a flexible window for intimacy. Because it is a moderate dose, it is often chosen based on individual response, tolerability, and medical advice. Common side effects may include headache, flushing, nasal congestion, dizziness, or upset stomach. These are usually mild and temporary. Less common but more serious side effects, such as prolonged erections (priapism), sudden changes in vision or hearing, or chest pain, require immediate medical attention.
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