01
The QT line is the gate, not a footnote under the price
Congenital long QT or a class IA or class III antiarrhythmic is a reason to avoid vardenafil entirely. Quinidine, procainamide, amiodarone, and sotalol are the names I ask for by mouth. A cheap 2.5 mg offer does not soften that line.
Most labelled starts sit at 10 mg, about 60 minutes before activity, once a day, with 20 mg as a ceiling and 5 mg as a step down. Sexual stimulation is still required. The 2.5 mg tablet is on the bottle because some men must start there, not because 2.5 mg is the usual first night.
The 2.5 milligram tablet exists for ritonavir (no more than 2.5 mg in 72 hours), for several other strong CYP3A4 inhibitors (2.5 mg in 24 hours), and as the lowest available step when a cautious start is written. Pricing it as 'the cheap Levitra' without that context is how the wrong man gets the right-looking box.
Nitrates and riociguat are banned here as they are on tadalafil. The QT chapter is extra work this molecule asks for. I do that work before I talk about a coupon.
02
Alpha-blockers want 5 mg, not a leap to 20
Stable alpha-blocker therapy precedes any vardenafil start. The film-coated label wants 5 mg in that setting, or 2.5 mg if a listed CYP3A4 inhibitor is also present. Turning up the alpha-blocker later can drop pressure again even if the PDE5 dose was quiet at first.
Terazosin forced-titration work showed enough standing-pressure outliers that the simultaneous-Tmax arm was stopped early in one design. Tamsulosin and alfuzosin were also studied. The lesson I keep is separation of peaks and a low start, not a casual 'they're often used together' wave.
Elderly men showed 34 percent higher Cmax and 52 percent higher AUC than younger men. That is a reason to be conservative with the first tablet in a man over 65, especially if an alpha-blocker is already on the list. It is not, by itself, a mandate to use 2.5 mg in every older man.
03
When 2.5 mg is the correct first tablet
| Situation | Labelled vardenafil film-coated start / cap |
|---|---|
| Most adults | 10 mg as needed; 5-20 mg range; once daily |
| Stable alpha-blocker | Start 5 mg (2.5 mg if a listed CYP3A4 inhibitor is also on) |
| Child-Pugh B | Start 5 mg; maximum 10 mg |
| Ritonavir | 2.5 mg; not again for 72 hours |
| Listed strong CYP3A4 inhibitors (not ritonavir) | 2.5 mg; not again for 24 hours |
| Ketoconazole / itraconazole 200 mg daily or erythromycin | 5 mg in 24 hours |
Ritonavir six hundred milligrams twice daily with vardenafil 5 mg raised AUC 49-fold and Cmax 13-fold and stretched the half-life to about 26 hours. The labelled answer is a single 2.5 mg tablet not more often than every 72 hours. That is not a bargain pack. It is a safety cap.
Indinavir, saquinavir, atazanavir, and ketoconazole or itraconazole at 400 mg daily, plus clarithromycin, share a 2.5 mg-in-24-hours cap. Indinavir with 10 mg vardenafil raised AUC 16-fold and Cmax 7-fold and roughly doubled the half-life. Those are label multiples, not guesses.
Ketoconazole two hundred milligrams daily with vardenafil 5 mg raised AUC 10-fold and Cmax 4-fold; the cap there is 5 mg in 24 hours. Erythromycin sits in that moderate-inhibitor band with a 5 mg daily cap. Grapefruit is expected to raise exposure even though it was not a formal study meal on this label.
Moderate hepatic impairment (Child-Pugh B) starts at 5 mg and must not exceed 10 mg. After 10 mg, Cmax and AUC were 130 percent and 160 percent higher than in controls. Child-Pugh C was not studied; I do not start vardenafil there. Mild impairment does not need an automatic cut.
04
Eight tablets of the lowest start, not a thirty-count board
Generic vardenafil 2.5 mg, eight tablets, the Myrto lowest labelled start, marked September 2026. GoodRx's Levitra table lists 2.5 mg x 30 at $1,100.46 average retail and $289.61 with a coupon. Those figures stay in this caption. Each link is that pharmacy only. Staxyn 10 mg ODT is a different fill. Myrto does not dispense. Prescription and a QT screen still come first. ZIP moves the number.
Eight tablets of two-point-five milligrams is the count this page asks a window to price. Published boards often show 2.5 mg times thirty. Ask them to price eight. Those thirty-count figures stay in the caption so you can see why the board and the script diverge.
A 'cheap Levitra 2.5 mg' search that skips the QT list and the inhibitor list is shopping the wrong object. The lowest tablet is a constrained start. It is not a starter pack for a first-time buyer with a normal ECG and no ritonavir.
Sixty minutes before activity is the labelled film-coated timing for most adults on 10 mg. A 2.5 mg start on ritonavir does not get a second tablet at sixty minutes if the first night felt quiet. The next allowed dose is 72 hours later, not an hour later.
Moderate hepatic impairment already used 5 mg as a start and 10 mg as a ceiling. A man in that band who also takes erythromycin needs the tighter of the two caps, not an average. I write the smaller number.
05
Headache and flush are ordinary. Four hours is not.
Flexible-dose trials started men at 10 mg and allowed 5 or 20 mg. Headache, flushing, rhinitis, and dyspepsia rose with dose. Back pain was close to placebo (2.0 percent versus 1.7 percent) and is not the delayed tadalafil story.
An erection lasting more than four hours is still an emergency. Sudden vision or hearing change is the same class warning as the other two profiles. I will not repeat the nitrate lecture here except to say it is a ban, not a 'use carefully.'
Alcohol at 0.5 g/kg with 20 mg vardenafil did not add a hypotensive effect in a four-hour volunteer window. Nifedipine-controlled men saw about 6/5 mmHg extra supine drop after 20 mg. Ordinary antihypertensives are a counseling point. Nitrates are not.
Aspirin, two 81 mg tablets, plus vardenafil 10 or 20 mg did not stretch bleeding time further in the labelled interaction work. That is not permission to ignore anticoagulants or a bleeding history. It is a specific negative finding, not a general 'blood thinner' clearance.
Pediatric patients are not an indication. The trials were not run in children. Women are not an ED indication on this label. I will not reframe a 2.5 mg strip as a shared couple's tablet.
Initial US approval for vardenafil hydrochloride tablets was 2003. Film-coated 2.5 mg tablets on the generic label I used are white to off-white, round, debossed L 50. Five, ten, and twenty milligram tablets on that same write-up are orange. Color is not a dose you guess in the dark.
06
A short clock with a small swallowed fraction
Absolute bioavailability is about fifteen percent. Fasted Tmax after 20 mg sits between 30 minutes and 2 hours, median 60 minutes. Terminal half-life of parent and M1 is about 4 to 5 hours. Clearance is about 56 L/h. Most of an oral dose leaves as metabolites in feces (about 91-95 percent), little in urine (about 2-6 percent).
High-fat meals cut Cmax by 18 to 50 percent in two food studies. The label still allows the tablet with or without food. I still ask men not to judge a first 2.5 or 10 mg night after a heavy plate. The hit is on peak height more than on a tidy extra hour, unlike the sildenafil food paragraph.
Volume of distribution is about 208 L. Protein binding is about 95 percent for parent and M1. M1 is a desethyl metabolite with about 28 percent of parent PDE5 potency in vitro and accounts for roughly 7 percent of total activity. CYP3A4 does most of the work, with CYP3A5 and CYP2C isoforms in the background.
Renal impairment down to low clearances raised AUC only about 20-30 percent in the studied bands. Dialysis patients were not characterized. I still want the creatinine in the room, but the big dose cuts on this label are hepatic and CYP3A4, not a routine renal step-down.
A mean 0.00018 percent of a 20 mg oral dose showed up in semen at 1.5 hours in healthy volunteers. That is a label curiosity, not a contraception method and not a reason to skip the QT walk. Cimetidine 400 mg twice daily did not change vardenafil AUC or Cmax after 20 mg.
Once-daily frequency still applies. A second film-coated tablet the same day because the first was taken after a heavy plate is an extra dose. Wait for the next calendar day. Do not stack 2.5 on 10 to 'catch up.'
07
Staxyn 10 mg melts. It is not this fill.
Orally disintegrating vardenafil ten milligrams is Staxyn. It sits on the tongue and does not need a glass of water. The label says it is not interchangeable with a 10 mg film-coated Levitra tablet because systemic exposure is higher with the melt.
Water is not required for Staxyn, and that convenience is the only reason some men ask for it. Convenience is not a reason to substitute it for a 2.5 mg film-coated start, or to stack a melt on a swallowed tablet. One product, one night.
Do not swap the melts for film-coated tablets milligram for milligram at a pharmacy window. If the script says Levitra 2.5 mg, the ODT is the wrong box. If the script says Staxyn, the 2.5 mg film-coated tablet is the wrong box. I will not price Staxyn on this page.
08
What the QT study actually showed
Fifty-nine healthy men received both a therapeutic 10 mg film-coated dose and an 80 mg supratherapeutic dose. Moxifloxacin 400 mg was the active control. QTc increases on vardenafil sat in a similar range to that control. A later pairing with another QT-active drug added to the effect instead of hiding it.
Quinidine, procainamide, amiodarone, and sotalol stay on the avoid list with congenital long QT. I also pause for other QT-prolonging drugs even when they are not in those two antiarrhythmic classes, because the label asks for a clinical decision there, not a shrug.
Additive QT with a second drug is the post-marketing lesson. 'It was only a small mean change in healthy men' is not a reason to give vardenafil to a man already on sotalol. If the ECG story is messy, pick another PDE5 inhibitor or pick no tablet.
Fainting, a new slow pulse, or a family story of sudden death belongs in the visit that happens before the first 2.5 mg tablet, not in a message sent after a cheap eight-count arrives.
Sildenafil also moved QTc a little in a related design. The vardenafil label is the one that then says men on class IA or III drugs, or with congenital long QT, should avoid the product. I treat that sentence as written. I do not dilute it because the mean change in healthy volunteers looked small.
09
If the QT walk fails, the 2.5 mg box stays shut
Walk the QT line, then decide whether 2.5 mg is even the right strength. For most men the honest start is still 10 mg. For a man on ritonavir or a listed azole, 2.5 mg is the cap, not a teaser dose on the way to 20. A coupon cannot move that cap. Only the ECG and the inhibitor list can open or shut the box.
Staxyn stays a separate product. The first-walk dispatch is the place for the ordinary 10 mg night after the ECG story is clean. A clinician who can see the antiarrhythmic list closes this, not a coupon.
Generic 2.5 mg film-coated vardenafil and brand Levitra 2.5 mg share this lock. Orange 10 and 20 mg tablets are other strengths. A white 2.5 mg round tablet is not Staxyn. If the box melts on the tongue, you have the wrong product for this page.