Levitra 40 mg (vardenafil 40 mg) for erectile dysfunction:

• 40 mg is higher than the usual recommended maximum dose. Standard vardenafil tablets are typically prescribed at 5 mg, 10 mg, or 20 mg, with 20 mg once in 24 hours generally being the maximum recommended dose. (Drugs.com)
• A 40 mg strength may exist in some markets under different brand names, but it should only be used if specifically prescribed by a clinician. (1mg)

How it’s usually taken

• About 30–60 minutes before sexual activity.
• Sexual stimulation is still needed for it to work.
• Avoid taking more than one dose in 24 hours. (Drugs.com)

Common side effects

• Headache
• Flushing
• Nasal congestion
• Indigestion
• Dizziness (Drugs.com)

Do not use vardenafil if you:

• Take nitrate medications (such as nitroglycerin) because the combination can cause a dangerous drop in blood pressure.
• Have been advised to avoid sexual activity because of certain heart conditions.
• Take certain medications or have liver disease, as dose adjustments may be needed. (Drugs.com)