Levitra 20 mg was developed by the pharmaceutical company Bayer/GlaxoSmithKline and uses Vardenafil HCl as main component of the medication. 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
Follow the directions for using this medicine provided by your doctor. This medicine comes with a patient information leaflet. Read it carefully. Ask your doctor, nurse, or pharmacist any questions that you may have about this medicine. Take this medicine orally as needed 1 hour before sexual activity or as directed by your doctor. Do not take this medicine more often than once daily as needed. If you are taking certain other medicines you may only be able to take this medicine one time every three days. Contact your doctor or pharmacist for more information. This medicine may be taken on an empty stomach or with food. However, taking this medicine with a high-fat meal may reduce the amount of medicine that your body absorbs. Avoid eating grapefruit or drinking grapefruit juice while being treated with this medicine unless your doctor instructs you otherwise.
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 20 mg 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).
If you think you have taken too much of this medicine contact a poison control center or emergency room at once. Symptoms of overdose include pain in the back, jaw, arm, blindness, blurred vision, chest pain or discomfort, decreased vision, blurred vision.
Possible side effect
Side effects that you should report to your prescriber or health care professional as soon as possible.
- back pain
- changes in hearing such as loss of hearing or ringing in ears
- changes in vision such as loss of vision, blurred vision, eyes being more sensitive to light, or trouble telling the difference between blue and green objects or objects having a blue color tinge to them
- chest pain or palpitations
- difficulty breathing, shortness of breath
- eyelid swelling
- muscle aches
- prolonged erection (lasting longer than 4 hours)
- skin rash, itching
Side effects that usually do not require medical attention (report to your prescriber or health care professional if they continue or are bothersome):
- stuffy nose
This list may not describe all possible side effects.
Do not take Levitra if you are taking the following medications:
- nitroglycerin-type drugs for the heart or chest pain such as amyl nitrite, isosorbide dinitrate, isosorbide mononitrate, nitroglycerin, even if these are only taken occasionally. This includes some recreational drugs called 'poppers' which also contain amyl nitrate and butyl nitrate.
Levitra 20 mg may also interact with the following medications:
- alpha blockers such as alfuzosin (UroXatral®), doxazosin (Cardura®), prazosin (Minipress®), tamsulosin (Flomax®), or terazosin (Hytrin®), used to treat high blood pressure or an enlarged prostate.
- arsenic trioxide
- certain antibiotics such as clarithromycin, erythromycin, sparfloxacin, troleandomycin
- certain medicines used for seizures such as carbamazepine, phenytoin, and phenobarbital
- certain medicines for the treatment of HIV infection or AIDS
- certain medicines to control the heart rhythm (e.g., amiodarone, disopyramide, dofetilide, flecainide, ibutilide, quinidine, procainamide, propafenone, sotalol)
- grapefruit juice
- medicines for fungal infections (fluconazole, itraconazole, ketoconazole, voriconazole)
- rifabutin, rifampin, or rifapentine
- some medicines for treating depression or mood problems (amoxapine, maprotiline, fluoxetine, fluvoxamine, nefazodone, pimozide, phenothiazines, tricyclic antidepressants)
Tell your prescriber or health care professional about all other medicines you are taking, including non-prescription medicines, nutritional supplements, or herbal products. Also tell your prescriber or health care professional if you are a frequent user of drinks with caffeine or alcohol, if you smoke, or if you use illegal drugs. These may affect the way your medicine works. Check with your health care professional before stopping or starting any of your medicines.