Ten to 20 mg as needed, after the QT line
Most men start film-coated vardenafil at 10 mg, taken about an hour before sex. The labelled range is 5 to 20 mg. Twenty milligrams is the ceiling. Men 65 and older often start at 5 mg. The tablet may be taken with or without food. A high-fat meal can still cut Cmax.
Congenital long QT and class IA or III drugs (quinidine, procainamide, amiodarone, sotalol) are a reason to refuse this lock. Vardenafil prolonged QTc in a dedicated study. Moxifloxacin 400 mg, the active control, moved the interval in a similar way. That is enough to keep this molecule off some charts where sildenafil might still be discussed.
Nitrates remain a never. Riociguat is the other pathway block. Do not stack this tablet with tadalafil or sildenafil in the same window. One PDE5 brake is the issue. Two is a duplicate.
Reviews that call Levitra 'just a stronger Viagra' skip the QT card and the Staxyn mismatch. Potency per milligram is real. It is not a reason to skip the screen. Cheap 10-20 mg pills that arrive without a history are not a review I would file.
Canadian and EU packs sometimes print a 25-to-60-minute window. The US film-coated start is still 'approximately 60 minutes'. I use the hour for planning. I do not promise a 25-minute onset to win a review.
Stepping 5, 10, and 20 on the film-coated card
CYP3A4 holds on the vardenafil card
- Ritonavir 600 mg b.i.d. + vardenafil 5 mg: AUC ×49, Cmax ×13, t½ ~26 h; max 2.5 mg / 72 h
- Indinavir 800 mg t.i.d. + vardenafil 10 mg: AUC ×16, Cmax ×7; max 2.5 mg / 24 h
- Ketoconazole or itraconazole 400 mg daily: max film-coated 2.5 mg once daily
- Ketoconazole or itraconazole 200 mg daily: max film-coated 5 mg / 24 h
- Staxyn: do not combine with moderate or potent CYP3A4 inhibitors at all
Stepping from 10 mg to 20 mg is the labelled move when 10 mg is tolerated and still thin after fair tries. Stepping to 5 mg is the move when flush or headache outweighs the gain. Two-point-five milligrams exists for the strong-inhibitor and alpha-blocker starts, not as a casual first shop.
Men over 65 often start at 5 mg on US film-coated labelling. Moderate hepatic impairment (Child-Pugh B) starts at 5 mg and should not exceed 10 mg. Severe hepatic impairment is not a vardenafil candidate I would issue. Renal dosing is less dramatic than with tadalafil, but the whole list still gets read.
Ritonavir is the extreme case. A 5 mg vardenafil dose with ritonavir 600 mg twice daily raised AUC 49-fold and Cmax 13-fold, and stretched half-life to about 26 hours. The film-coated cap in that setting is 2.5 mg once in 72 hours. Staxyn is simply not used.
Indinavir multiplied AUC sixteen times and Cmax seven times after 10 mg vardenafil, with a doubled half-life. The film-coated cap with indinavir or other potent inhibitors is 2.5 mg once daily. Ketoconazole 200 mg daily pairs with a 5 mg cap. Those are label numbers, not bench guesses.
The QT study in 59 men, without the brochure gloss
| Arm (1 h post-dose) | What the QT work showed |
|---|---|
| Vardenafil 10 mg FCT | QTc rise similar to moxifloxacin 400 mg; +5 bpm vs placebo |
| Vardenafil 80 mg | Supratherapeutic cover for ritonavir-level exposure; +6 bpm |
| QTcF vs placebo (EU text) | +8 msec at 10 mg; +10 msec at 80 mg |
| With gatifloxacin 400 mg | Additive ~4 msec vs either drug alone |
| Who we refuse | Congenital LQTS; class IA / III antiarrhythmics |
Fifty-nine healthy men took 10 mg and 80 mg vardenafil in a crossover with placebo and moxifloxacin 400 mg. Ages were 45 to 60. QT was read at one hour, near usual Tmax. The 80 mg dose is four times the labelled ceiling. It was chosen to cover levels seen when 5 mg meets ritonavir.
Moxifloxacin 400 mg was the active control because a negative study against a silent control would not have been credible. Therapeutic 10 mg and supratherapeutic 80 mg both lengthened QTc by methods that roughly matched the moxifloxacin arm. Heart rate rose about 5 beats/min after 10 mg and about 6 after 80 mg.
European prescribing text reports a mean QTcF increase of 8 msec (90% CI 6-9) at 10 mg and 10 msec (90% CI 8-11) at 80 mg versus placebo at one hour. A later pairing with gatifloxacin 400 mg showed an additive QTc effect of about 4 msec versus either drug alone. The clinical meaning of those milliseconds is uncertain. The prescribing consequence is not.
Skip this lock when a congenital long-QT diagnosis is on the chart, or when a class IA or III antiarrhythmic is already in the weekly box. Other QT-prolonging drugs are a judgement call, not a shrug. I would rather issue sildenafil 50 mg than pretend the vardenafil study did not happen.
Ask the window to price six of 20 mg, not the ten-count board
Generic vardenafil 20 mg, six tablets, the labelled ceiling of the Advena 10-20 mg as-needed lock, marked September 2026. GoodRx's Levitra table lists 20 mg x 10 at $573.78 average retail and $44.21 with a coupon. Those figures stay in this caption. Each link is that pharmacy only. Staxyn 10 mg ODT is a different fill. Advena does not dispense. Prescription and a QT screen still come first. ZIP moves the number.
Six tablets of 20 mg is the labelled ceiling of this lock, counted for a short first run. The quote card below sets that count against the nearest published GoodRx line, which is 20 mg by ten. Ask the window to price six. Do not pay a ten-count coupon against a six-count bag and call it a match.
Costco, Publix, Sam's Club, and Target are the four official pharmacy pages on this card. Each href is that chain only. GoodRx stays in the caption. Advena does not dispense. A prescription and a QT screen still come first.
Staxyn 10 mg ODT is a different fill. Do not let a substitution engine swap the melt for film-coated 10 mg, or the reverse, to hit a coupon. Generic vardenafil 10 mg by a larger count is a valid script. It is not the quote this page published.
Cheap Levitra 10-20 mg pills without a history are the reviews I throw out. Counterfeit film-coated tablets exist in this class. A price that undercuts every grocery window and never asks about amiodarone is not a win. ZIP still moves a real quote.
Prescription reviews worth reading name the strength, the count, and whether anyone asked about QT drugs. A star rating on a 20 mg six-count does not transfer to Staxyn. It does not transfer to a 10 mg thirty-count either.
Absorption is fast. Bioavailability is not generous.
Absolute bioavailability is only about 15 percent. That is leaner than sildenafil's 41 percent mean. Median Tmax after a 20 mg fasted dose is 60 minutes, range 30 minutes to 2 hours. The clinical window people describe is a few hours, not a 36-hour plateau.
Terminal half-life of parent and the M1 metabolite is about 4 to 5 hours. Clearance is about 56 L/h. Volume of distribution is about 208 L. Protein binding is about 95 percent for parent and M1. Recovery in semen after 20 mg was a trace (0.00018 percent of the dose at 1.5 hours).
High-fat meals cut Cmax by 18 to 50 percent in two food studies. AUC and Tmax were less moved than with sildenafil's 29 percent Cmax cut plus a full hour of Tmax delay, but a heavy plate can still blunt the peak. If the first 10 mg felt empty after a late dinner, repeat fasted before you step to 20 mg.
Excretion is almost all as metabolites in feces (about 91-95 percent of the oral dose). Urine carries about 2-6 percent. CYP3A4 does the heavy work, with CYP3A5 and CYP2C9 contributing. That map is why the fold-increases above are so large, and why a 'just take 10 mg anyway' plan on ritonavir is reckless.
M1 is an active metabolite. It does not change the once-daily cap. It does help explain why a strong CYP3A4 block lasts into the next calendar day. I treat leftover vardenafil after ritonavir as still present, not as a cleared Friday tablet.
Headache, flush, and the trial scores at 10 and 20 mg
Headache and flushing lead the ≥2 percent list, with nasal congestion, dyspepsia, sinusitis, dizziness, nausea, and back pain. Placebo-controlled trials showed a dose effect for headache, flushing, dyspepsia, nausea, and rhinitis across 5, 10, and 20 mg. That is why a man who flushed hard on 20 mg should not be told to 'push through' at the same strength.
North American fixed-dose work at 3 months put SEP2 (penetration) at 65, 75, and 80 percent on 5, 10, and 20 mg, against 52 percent on placebo. SEP3 (maintenance to intercourse) was 51, 64, and 65 percent against 32 percent on placebo. The European trial lined up. Those are group rates, not a promise for Friday.
Diabetes and post-prostatectomy cohorts were harder, as expected. In diabetes, SEP2 was 61 percent on 10 mg and 64 percent on 20 mg versus 36 percent on placebo. SEP3 was 49 and 54 percent versus 23 percent. After prostatectomy, SEP2 sat near 47-48 percent versus 22 percent, and SEP3 near 37 and 34 percent versus 10 percent.
Priapism is uncommon and still a 4-hour emergency. Sudden vision or hearing loss is a stop. Alpha-blockers plus vardenafil can drop standing pressure enough to faint; the terazosin simultaneous-Tmax arm of one study was stopped early for standing systolic values under 85 mm Hg. Start one vasodilator at a time.
Four major fixed-dose trials enrolled 2,431 men aged 20 to 83, mean age 57. Two were general ED, one diabetes, one post-prostatectomy. Primary reads sat at three months on the IIEF erectile-function domain and on SEP2 and SEP3. That is the evidence card, not a shop review.
Staxyn 10 mg is not a film-coated 10 mg
Staxyn 10 mg dissolves on the tongue. The label says it is not interchangeable with vardenafil 10 mg film-coated tablets. The melt gives higher systemic exposure than Levitra 10 mg. Swapping them one-for-one is a dosing error.
Exposure after the melt tablet is the reason Staxyn is a single 10 mg strength. You do not titrate Staxyn to 20 mg. You do not start Staxyn in a man already on an alpha-blocker. Film-coated 2.5 mg or 5 mg is the labelled on-ramp in that setting. A later switch to Staxyn is a prescriber call.
Do not use Staxyn with moderate or potent CYP3A4 inhibitors. Erythromycin, clarithromycin, ketoconazole, itraconazole, and the protease inhibitors are on that list. Grapefruit juice is named on the Staxyn interaction panel. The melt has no room to step down.
This page's fill is film-coated 20 mg by six, the ceiling of the 10-20 mg lock. A Staxyn blister is a different NDC and a different quote. If chewing or swallowing is the only reason someone wants the melt, say so on the script. Do not silently substitute.
Place the melt on the tongue and let saliva finish it. Do not chase it with a glass of water while it is still a tablet. The film-coated 10 mg is a swallow. Mixing those instructions is how people invent a third, unlabelled product.
Potency per milligram is not a reason to skip the screen
Issue 10 mg film-coated if the QT line is clean, nitrates are absent, and the man can take the work of sex. Step to 20 mg only after a fair, preferably fasted, try. Step to 5 mg when the flush is the story. Leave Staxyn on its own card.
Mail [email protected] when a bottle and this sheet disagree. Dr. Lena Hofer holds the Vienna bench. The mailbox does not prescribe. A clinician who can see the ECG and the drug list still has to sign.
If you wanted a meal-proof 36-hour plateau, use the tadalafil 10-20 mg lock. If you wanted the usual 50 mg start and a food briefing, use the sildenafil sheet. The PDE5 comparison keeps the three locks from collapsing into one shopping adjective.
Six of 20 mg is a short run of the ceiling, not a monthly habit. If 10 mg was never tried, do not fill the ceiling first just because the quote card shows twenty.