When the level actually peaks
After a single 20 mg dose in healthy volunteers who had not eaten, the peak usually arrived between 30 minutes and 2 hours. The median was 60 minutes. That is why about an hour before sex is the habit on the label, and why a swallow ten minutes before is too early to grade the tablet.
The terminal half-life of vardenafil and its primary metabolite is approximately 4 to 5 hours. Plan on one evening, not a tablet that stays available through the next day. There is no daily-use schedule on this film-tablet label. A morning tablet meant to sit in the background belongs to a different product. The tadalafil note is the page for that schedule. The access checks and the rest of the vardenafil holds sit on the vardenafil medicine page.
Food is allowed, and a fatty plate can still quiet the peak
Levitra can be taken with or without food. In two food-effect studies, high-fat meals cut the peak concentration by 18% to 50%. The tablet is still permitted after that meal. The peak may simply be lower, so one greasy dinner is a poor night on which to decide the dose failed.
Do not answer a quieter peak by taking another tablet later the same day. The maximum recommended dosing frequency is once per day. If rich dinners are the usual evening, say that to the prescriber before anyone climbs from 10 mg to 20 mg. Twenty milligrams is the labeled ceiling after a real trial of the start dose. It is not a way to outrun the plate.
Some clinics outside the United States open lower than 10 mg. This page follows the US film-tablet label, where most adults start at 10 mg.
When the first tablet should be smaller
Age 65 or older: a starting dose of 5 mg should be considered. In healthy volunteers, mean peak concentration was 34% higher and overall exposure was 52% higher in men 65 or older than in men aged 18 to 45. The lower start is that finding, written as a dose.
Moderate liver impairment (Child-Pugh B): start at 5 mg, and do not go above 10 mg. After a 10 mg dose in that group, peak and overall exposure were much higher than in people with a healthy liver. Severe hepatic impairment (Child-Pugh C) was not studied. The label does not recommend Levitra there until more is known.
An alpha-blocker already on the list: both drugs lower blood pressure, and together they can drop it enough to cause fainting. The patient counseling line is to start Levitra at the lowest recommended dose, not at an automatic 10 mg. Tell the prescriber who knows both medicines before the first swallow.
Some antivirals and antifungals shrink the dose further, because they raise vardenafil levels. Ritonavir lengthens the half-life about five- to six-fold. No more than a single 2.5 mg dose in a 72-hour period. Indinavir, saquinavir, atazanavir, clarithromycin, ketoconazole 400 mg daily, or itraconazole 400 mg daily: do not exceed 2.5 mg once a day. Ketoconazole 200 mg daily or itraconazole 200 mg daily: do not exceed a single 5 mg dose in 24 hours.
Grapefruit juice was not run as its own pairing study. The label still groups it with other CYP3A4 inhibitors and says it would likely increase vardenafil exposure. A daily grapefruit habit belongs on the list before the first 10 mg.
Mild, moderate, or severe kidney impairment does not, on this label, require its own dose change. Dialysis was not studied, and use is not recommended there until more is known.
Stops that outrank the hour
Nitrates, taken regularly or only now and then, and nitric oxide donors are contraindicated with Levitra. The patient leaflet names nitroglycerin tablets, sprays, ointments, pastes, and patches, and also isosorbide dinitrate and isosorbide mononitrate. It also says not to use recreational poppers such as amyl nitrate and butyl nitrate. Taken together, blood pressure can fall hard enough to cause dizziness, fainting, a heart attack, or a stroke.
A suitable time interval after Levitra for a later nitrate has not been determined. Do not invent a two-hour or twenty-four-hour gap from this page. If chest pain starts after a dose, the people treating it need to know when the tablet was taken. That is emergency care, not a home calculation.
Class 1A antiarrhythmics (quinidine, procainamide), Class III antiarrhythmics (amiodarone, sotalol), and congenital QT prolongation: avoid Levitra. A single-dose study in healthy men measured the QT interval about an hour after 10 mg and after 80 mg. The clinical meaning of those QT changes is unknown. The practical instruction is still to stay off the drug when the QT list is already occupied. Trial scores and that QT study are unpacked on the Levitra evidence note.
Known hypersensitivity to any component of the tablet is also a contraindication.
If the effect lasts too long, or vision changes
Rare reports for this class, including vardenafil, include erections longer than 4 hours and priapism, described as a painful erection longer than 6 hours. If an erection lasts longer than 4 hours, get medical help immediately. Untreated priapism can injure the tissue.
Stop Levitra, and the other PDE5 inhibitors, and get medical attention for sudden loss of vision in one or both eyes. The label discusses rare reports of non-arteritic anterior ischemic optic neuropathy and says it is not possible to tell whether the drug itself caused those events. The instruction to seek care does not wait on that answer.
Alcohol, in the amount the label actually tested
In healthy volunteers, alcohol at 0.5 g/kg (about 40 mL of absolute alcohol in a person weighing 70 kg) did not change vardenafil levels when the two were taken together. Levitra 20 mg did not add to alcohol's blood-pressure effect during a 4-hour watch in that same test. That is a specific study, not permission for a heavy night, and not proof that a larger amount is neutral.
One pass through the evening
| Situation | What the US film-tablet label supports |
|---|---|
| Most adults | 10 mg by mouth about 60 minutes before sex, once that day, with or without food |
| Age 65 or older | Consider 5 mg as the start |
| Moderate liver impairment | 5 mg start, and do not exceed 10 mg |
| Already taking an alpha-blocker | Lowest recommended start, because blood pressure can stack |
| Ritonavir | A single 2.5 mg dose, then not again for 72 hours |
| Ketoconazole or itraconazole 400 mg daily, or the potent antivirals named above | Do not exceed 2.5 mg once a day |
| Ketoconazole or itraconazole 200 mg daily | Do not exceed 5 mg in 24 hours |
| High-fat meal | Still allowed; peak may fall 18% to 50%; do not take a second tablet |
| Nitrate, popper, or the QT drugs named above | Do not take Levitra |
Judge the 10 mg start across more than one properly timed evening before anyone calls the dose a failure. A single late swallow after a very fatty meal is a weak test. Raising the dose, or switching molecules, is a conversation with the prescriber who has the rest of the list.
Where the brand came from, and why a later melt is not this swallow, is the Levitra history note. Neither that note nor this one is a prescription.
Do not start, stop, or change vardenafil from a library page. Bring the timing, the meal, and the medicine list to the clinician who can see you.