The 10 mg start and the 60-minute mark
On the DailyMed Levitra label (setid 4e66ad5c-572c-4819-8b6e-6930c33cc210), dosage and administration sets 10 mg as the starting dose for most patients. Some men notice effect earlier than an hour. The counseling line is still about 60 minutes before sexual activity, with stimulation. Ten minutes and no erection is not a verdict on the tablet.
Terminal half-life is about 4 to 5 hours. That fact does not create a second allowed dose after dinner. The frequency rule is once per day.
The 20 mg strength is the labeled ceiling when 10 mg was timed honestly and side effects allow a climb. The 5 mg strength is a down-step, not a default 'gentle' night. Your prescriber owns which step applies. This page does not.
What a high-fat meal does to the peak
Food is allowed. A high-fat meal is the variable that changes the peak: Cmax down 18% to 50% in the two food-effect studies on this label. The text does not give a separate minute count for a delayed Tmax, so this page does not invent one. What you can use at the table is simpler. A heavy, fatty plate can blunt the peak that the one-hour plan expects.
If that plate is already eaten, wait out the meal and judge the night on one tablet. Swallowing another 10 mg at minute forty stacks a dose the label does not offer. Alcohol on top of a vasodilator adds dizziness when you stand up. It does not repair a greasy meal.
A fair first test is dull on purpose: the prescribed milligram, one swallow, a real attempt at sexual activity, and an honest read of what you ate. Several evenings on that rule belong in the conversation before anyone moves from 10 mg to 20 mg.
When the label steps the dose down
| Situation on this label | What the dosage section says |
|---|---|
| Most patients | Start 10 mg, about 60 minutes ahead, once a day |
| Age 65 and older | Consider a 5 mg start |
| Child-Pugh B | Start 5 mg; do not exceed 10 mg |
| Child-Pugh C or dialysis | Not evaluated; use not recommended |
| Ritonavir | Single dose not above 2.5 mg in 72 hours |
| Stable alpha-blocker | Start at 5 mg once the alpha-blocker is stable |
Age 65 and older: mean Cmax about 34% higher and AUC about 52% higher than in men 18 to 45. A starting dose of 5 mg should be considered. Moderate hepatic impairment (Child-Pugh B) after a 10 mg dose: Cmax up 130% and AUC up 160%. Start at 5 mg and do not exceed 10 mg. Severe hepatic impairment (Child-Pugh C) was not studied; use is not recommended.
Mild, moderate, and severe renal impairment do not require a dose change on this label. Dialysis was not studied; use is not recommended there either. Mild hepatic impairment (Child-Pugh A) needs no adjustment.
Stable alpha-blocker therapy comes first. LEVITRA then starts at 5 mg (2.5 mg if certain CYP3A4 inhibitors are also on board). The combination can drop blood pressure enough to cause fainting. Men who are unstable on the alpha-blocker alone are the wrong candidates for adding a PDE5 inhibitor.
Ritonavir is the steep interaction: do not exceed a single 2.5 mg dose in any 72-hour period. Indinavir, saquinavir, atazanavir, ketoconazole 400 mg daily, itraconazole 400 mg daily, and clarithromycin: do not exceed 2.5 mg in 24 hours. Ketoconazole 200 mg daily, itraconazole 200 mg daily, and erythromycin: do not exceed 5 mg in 24 hours. Those ceilings are not optional kitchen math.
Nitrates, poppers, and the QT avoid list
Administration with nitrates, regularly or intermittently, and with nitric oxide donors is contraindicated. Patient information names nitroglycerin in tablets, sprays, ointments, pastes, or patches, plus isosorbide dinitrate and isosorbide mononitrate, and poppers such as amyl nitrate and butyl nitrate. PDE5 inhibition can potentiate the blood-pressure drop from nitrates. The label states that a suitable interval after LEVITRA for safe nitrate use has not been determined.
A study in 18 healthy subjects did see extra blood-pressure effects when 20 mg was taken 1 or 4 hours before 0.4 mg sublingual nitroglycerin, and extra heart-rate effects at 1, 4, and 8 hours. Additional changes were not detected when 20 mg was taken 24 hours before that nitroglycerin dose. People who keep a nitrate for chest pain should not use that healthy-volunteer gap as permission. If emergency care is needed, say when the tablet was taken.
QT: in 59 healthy men, 10 mg and 80 mg produced QTc increases similar to moxifloxacin 400 mg (Fridericia means about 8 msec and 10 msec at one hour). A combination study showed an additive QTc effect. Avoid the drug if you take quinidine, procainamide, amiodarone, or sotalol, or if you have congenital QT prolongation. Later US labeling also contraindicates guanylate cyclase stimulators such as riociguat; this setid's contraindication block centers on nitrates and hypersensitivity, so read the bottle in your hand.
An erection lasting more than 4 hours needs emergency care. Sudden vision loss or sudden hearing loss means stop the PDE5 inhibitor and contact a doctor. Common effects on the patient page are headache, flushing, stuffy or runny nose, indigestion, upset stomach, and dizziness. They usually fade in a few hours. They are not a reason to add a second tablet.
Buying Levitra is a different page
How to take the tablet and how to obtain it are separate jobs. Sites that offer Levitra with no prescription, or that photograph a mystery blister next to a percent-off claim, sit on the warning side of the FDA consumer update on buying medicines safely from an online pharmacy. A legal US path still starts with a prescription and a pharmacy licensed in your state.
Brand Levitra tablets were later discontinued. FDA determined that was not for reasons of safety or effectiveness. A generic vardenafil tablet from a licensed pharmacy can be the fill; the imprint will not match the old Bayer cross. The origin of that brand exit is on the history note. The online permission checks are on the compound page.
This URL stops at administration: clock, plate, dose ceilings, nitrate stop, QT avoid list. It does not ship tablets and it does not quote a cash price.
Questions people ask next
How long before sex should I take Levitra? About 60 minutes for most men on this label. One dose only. Doses at least 24 hours apart.
Can I take vardenafil with food? Yes. A high-fat meal can cut Cmax by 18% to 50%. Do not answer a heavy plate with a second tablet.
What if nothing happens in 15 minutes? That is early. The fasted peak after 20 mg is usually somewhere between 30 minutes and 2 hours. Stimulation still has to happen.
I am 68. Do I start at 20 mg? The label says a 5 mg start should be considered at age 65 and older, because exposure runs higher. The prescriber confirms it.
I have nitroglycerin in the drawer. Is 24 hours enough? No home interval is given. Nitrates are contraindicated, and the label says a suitable safe interval has not been determined.
I take sotalol. Can I just use 5 mg? No. Class III antiarrhythmics are on the avoid list. A smaller tablet does not erase that line.
Where do I read about buying it online? The compound page. This card is timing and stops only.