Levitra is used to treat erectile dysfunction, which is a man's inability to maintain an erection. It works by relaxing muscles in the penis, allowing more blood to flow to it. The active ingredient in Levitra is vardenafil. The medication was first made available in 2003, and in the United States, you can only obtain it with a prescription. Levitra is taken on an as-needed basis, about one hour before you want to have sex. Alcohol and grapefruit should be avoided when taking this medication as they can produce severe side effects.

Common use
Levitra is an oral drug used to treat erectile dysfunction. Sexual stimulation causes the production and release of nitric oxide from the nerves endings of the cavernous bodies of the penis hereby activating enzyme guanylate cyclase. Guanylate cyclase in its turn is responsible for production of cyclic guanosine monophosphate (cGMP). The cGMP causes widening and relaxation of the blood vessels carrying blood to the penis. Levitra prevents phosphodiesterase-5 enzyme from destroying cGMP and thus helps to support blood flow to the penis.

Dosage and direction
The recommended dose of Levitra is 10 mg per day taken an hour before intercourse. If no side effects are experienced the dosage can be increased up to 20 mg. In case of adverse effects the dose is reduced to 5 mg daily. Do not take more than one tab of Levitra a day.

Precautions
Levitra has not been studied in people with cardiovascular disease, so it is preferable to avoid Levitra if in patients who have a stroke or heart failure, or a heart attack in history and especially within last six month. Before to take Levitra inform your doctor if you have kidney or liver problems, a bleeding disorder, stomach ulcer, or an inherited retinal disorder such as retinitis pigmentosa, allergic reaction to this medicine or any other medicines, deformation of the penis such as angulation, cavernous fibrosis (Peyronie's disease), as well as in diseases that contribute to the development of priapism (sickle-cell anemia, multiple myeloma, leukemia, or leukemia).

Contraindications
Levitra is contraindicated in patients with hypersensitivity to its ingredients, ones treated with organic nitrates, in patients under 16 y.o., or those who take HIV protease inhibitors such as indinavir and ritonavir.

Possible side effect
Levitra is usually well tolerated and side effects if occur are transient. The most frequent side effects are: headache, flushing (hyperemia of the person); frequent; dizziness, diarrhea phenomenon, nausea, nasal congestion. More rare and uncommon adverse effects are photosensitivity of skin, hypertension, back pain, watery eyes, hypotension, myalgia, priapism.

Drug interaction
Levitra's metabolism is inhibited by erythromycin, ketoconazole (Nizoral), itraconazole (Sporanox), indinavir (Crixivan) and ritonavir (Norvir). Levitra reduces the concentration of ritonavir and indinavir. In patients treated with nitrates Levitra may aggravate chest pain by increasing heart rate and lowering blood pressure. Levitra is able to exaggerate the blood pressure lowering effects of alpha-blocking drugs (terazosin or Hytrin). Levitra never should be administered in patients who are treated with organic nitrates.

Missed dose
Levitra is taken when needed but not more often than once daily so missed dose is not supposed.

Overdose
Symptoms of overdose include pain in the back, jaw, arm, blindness, blurred vision, chest pain or discomfort, decreased vision, blurred vision.

Storage
Store at room temperature between 15-30 C (59-86 F) away from children, pets, moisture and sunlight.

Disclaimer
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