When to refer

Customers should seek medical advice or be referred to their GP when they:

• Have taken the maximum dosage with no improvement in condition.
• Suffer seizure or convulsions.
• May have serious skin conditions such as Stevens-Johnson syndrome and Toxic epidermal necrolysis (TEN syndrome).
• Serious allergic reaction, symptoms such as sudden breathlessness or difficulty breathing, swelling of the face, mouth or lips.
• Sudden loss of vision.
• Have suffered a prolonged (lasting more than four hours) or painful erection.
• Unexplained chest pain during or after intercourse