Mid-start at five milligrams, with a QT line attached

01Why this letter files five milligrams first

Open on the mid-start. The usual 10 mg sentence stays visible so nobody pretends 5 mg is the universal first tablet for every adult.

Five milligrams is the step this site locked, not because the FDA made it the default for every adult. Section 2.1 still starts most men at 10 mg, with a rise to 20 mg or a cut to 5 mg based on effect and side effects. Once per day is the frequency limit.

The 5 mg row is where this despatch spends its ink: age 65 or older (consider 5 mg), Child-Pugh B (start 5 mg, maximum 10 mg), stable alpha-blocker therapy (start 5 mg; 2.5 mg if certain CYP3A4 inhibitors are also present), and the man who already found 10 mg too much.

Orange round 5 mg tablets (example deboss L 51 on some generics) sit between white-to-off-white 2.5 mg and the orange 10 mg and 20 mg siblings. Ordering 'Levitra online' without naming 5 mg is how a mid-start becomes a 10 mg default you did not want.

Stimulation is required. Absolute bioavailability is only about 15 percent. That low oral fraction is a PK fact, not a reason to double the tablet an hour later.

02Two-point-five, ten, and twenty still have labelled jobs

Two-point-five milligrams is the floor for several CYP3A4 prisons: ritonavir (no more than 2.5 mg in 72 hours), and a 24-hour 2.5 mg cap with indinavir, saquinavir, atazanavir, ketoconazole 400 mg daily, itraconazole 400 mg daily, or clarithromycin.

Ten milligrams remains the usual start for men who are not on those lists and not in the 65-plus or Child-Pugh B buckets this letter highlights. Twenty milligrams is the labelled ceiling. Flexible-dose trials started everyone at 10 mg and allowed a cut to 5 mg or a rise to 20 mg.

Staxyn 10 mg orodispersible tablet is a different formulation with its own food and water studies. Do not price an ODT as if it were eight film-coated 5 mg tablets. The fill card on this page is generic 5 mg film-coated, eight-count, versus GoodRx's published 5 mg x 30 line.

North American fixed-dose work in 762 men put 3-month EF domain scores at 18, 21, and 21 on 5, 10, and 20 mg versus 15 on placebo. SEP2 (penetration) was 65, 75, and 80 percent versus 52 percent. Five milligrams already separated from placebo. It is not a homeopathic step.

03Ritonavir stretched the half-life to 26 hours

Ritonavir 600 mg twice daily plus vardenafil 5 mg raised vardenafil AUC 49-fold and Cmax 13-fold and prolonged half-life to 26 hours. The labelled remainder is a single 2.5 mg tablet in a 72-hour period. A 5 mg mid-start is already too high on that background.

Ketoconazole 200 mg daily plus vardenafil 5 mg raised AUC 10-fold and Cmax 4-fold; cap at 5 mg in 24 hours. Ketoconazole 400 mg daily drops the cap to 2.5 mg in 24 hours. Erythromycin 500 mg three times daily raised AUC 4-fold and Cmax 3-fold; cap at 5 mg in 24 hours.

Indinavir 800 mg three times daily plus vardenafil 10 mg raised AUC 16-fold, Cmax 7-fold, and doubled half-life; cap at 2.5 mg in 24 hours. Cimetidine 400 mg twice daily did not change vardenafil AUC or Cmax with a 20 mg dose.

Elderly men (65 or older) showed Cmax 34 percent higher and AUC 52 percent higher than men 18 to 45. That is the PK behind the consider-5 mg geriatric sentence. Child-Pugh B after 10 mg: Cmax +130 percent, AUC +160 percent. Child-Pugh C was not studied. Severe hepatic disease is not a casual 5 mg experiment.

04Nitrates stay forbidden even after the 24-hour volunteer line

Sublingual nitroglycerin 0.4 mg taken 1 and 4 hours after vardenafil 20 mg in healthy middle-aged men showed potentiated blood-pressure drops; heart-rate increases were seen at 1, 4, and 8 hours. Those effects were not seen when the 20 mg tablet was taken 24 hours before the nitrate. The contraindication still stands for patients. Ischemic-heart-disease potentiation was not evaluated.

Single 20 mg doses in men with ED produced a mean maximum supine drop of 7 mm Hg systolic and 8 mm Hg diastolic versus placebo, with a mean heart-rate rise of 4 beats per minute, nadir between 1 and 4 hours. Day-31 repeats looked like day 1.

Nifedipine 30 or 60 mg plus vardenafil 20 mg added 6/5 mm Hg extra supine reduction in men whose hypertension was already controlled. Alpha-blocker work with terazosin, tamsulosin, and alfuzosin is why 5 mg (or 2.5 mg with certain CYP3A4 inhibitors) is the PDE5 start only after the alpha-blocker is stable. Simultaneous Tmax with terazosin produced enough standing SBP under 85 mm Hg that an arm was stopped early.

Alcohol 0.5 g/kg with vardenafil 20 mg did not potentiate hypotension over 4 hours in healthy volunteers. That volunteer line does not make 5 mg a drinking tablet.

Vardenafil 20 mg did not prolong bleeding time alone and did not add to aspirin's bleeding-time increase (two 81 mg tablets) in the interaction work. Men with bleeding disorders or significant active peptic ulcer still need a benefit-risk talk, because those groups were not treated as a routine cohort.

05Diabetes and prostatectomy numbers sit on 10 and 20

Harder cohorts did not receive a 5 mg randomized cell. Quote them that way.

Diabetes trial enrolled four hundred thirty-nine men (mean age 57, range 33 to 81) on fixed 10 mg or 20 mg versus placebo. EF domain landed at 17 on 10 mg and 19 on 20 mg versus 13 on placebo. This letter's 5 mg lock was not a randomized arm in that diabetes study.

SEP2 in that diabetes cohort was 61 percent on 10 mg and 64 percent on 20 mg versus 36 percent on placebo. SEP3 (maintenance to successful intercourse) was 49 percent and 54 percent versus 23 percent. Those are labelled special-population reads, not forum averages.

Radical prostatectomy study enrolled four hundred twenty-seven men (mean age 60, range 44 to 77), again at 10 mg and 20 mg. EF domain reached 15 versus 9 on placebo for both active doses. SEP2 was 47 and 48 percent versus 22 percent. SEP3 was 37 and 34 percent versus 10 percent.

Those special-population arms used the higher film-coated strengths. A 5 mg mid-start for a 65-year-old or a Child-Pugh B man is still a labelled first tablet. It is not the dose that generated the diabetes and prostatectomy tables. Do not quote 5 mg SEP3 from those two trials; the numbers are not there.

General-population SEP3 in the North American trial did include 5 mg: 51 percent versus 32 percent placebo, with 64 and 65 percent on 10 and 20 mg. That is the honest 5 mg efficacy line to carry next to the mid-start lock.

06Fifty-nine men, two doses, and a moxifloxacin control

A single-dose, double-blind, randomized, placebo- and active-controlled crossover in 59 healthy men aged 45 to 60 (81 percent White, 12 percent Black, 7 percent Hispanic) measured QT one hour after 10 mg and after 80 mg vardenafil. Eighty milligrams is four times the highest recommended dose; it was chosen to cover concentrations seen when 5 mg meets ritonavir 600 mg twice daily.

Heart rate rose a mean 5 beats per minute on 10 mg versus placebo and 6 beats per minute on 80 mg. Therapeutic and supratherapeutic vardenafil, and moxifloxacin 400 mg, produced similar QTc increases. No single correction method (Fridericia versus a linear individual correction) is declared more valid.

European product information reports a placebo-corrected QTcF increase of 8 msec (90 percent CI 6 to 9) at 10 mg and 10 msec (90 percent CI 8 to 11) at 80 mg at one hour. A later combination study with another QT-active drug showed an additive effect.

Patients with congenital long QT, or those on Class IA agents (quinidine, procainamide) or Class III agents (amiodarone, sotalol), should avoid vardenafil. That is a class-specific caution this molecule carries more loudly than the sildenafil start letter. The QT checklist postscript keeps the ECG list.

07Headache and flushing still climb from 5 to 20

Placebo-controlled trials suggested a dose effect for headache, flushing, dyspepsia, nausea, and rhinitis across 5, 10, and 20 mg. The pooled list of reactions at 2 percent or more also includes nasal congestion, sinusitis, flu syndrome, dizziness, increased creatine kinase, and back pain (2.0 percent versus 1.7 percent placebo).

Four major fixed-dose trials enrolled 2,431 men aged 20 to 83 (mean 57), including a diabetes trial and a post-prostatectomy trial. Primary reads were IIEF EF domain, SEP2, and SEP3 at 3 months. All three doses beat placebo. Mean baseline EF domain was 11.8.

Renal impairment with creatinine clearance 30 to 50 or under 30 mL/min raised vardenafil AUC about 20 to 30 percent versus clearance over 80. Dialysis pharmacokinetics were not evaluated. That is a smaller renal story than tadalafil's hard 20 mg closures, but it is not 'ignore the eGFR.'

Priapism, sudden vision loss (NAION class warning), and sudden hearing loss are the same emergency stops as the rest of the class. An erection past 4 hours is not a 5 mg success story.

08High-fat supper can cut Cmax by up to half

Fasted Tmax after a 20 mg dose in healthy volunteers usually falls between 30 minutes and 2 hours, median 60 minutes. Two food-effect studies showed high-fat meals reduce Cmax by 18 to 50 percent. The film-coated tablet may still be taken with or without food.

That Cmax haircut is why a 5 mg mid-start swallowed after a heavy plate can look like 'Levitra is weak' when the experiment was a blunted peak. The label's 60-minute lead assumes you are not fighting a 50 percent Cmax drop.

Mean steady-state volume of distribution is 208 L. Parent and M1 are about 95 percent protein-bound. After 20 mg, a mean 0.00018 percent of the dose appeared in semen at 1.5 hours. Terminal half-life of vardenafil and M1 is about 4 to 5 hours.

M1, the desethyl metabolite, circulates at about 26 percent of parent concentrations and holds about 28 percent of parent PDE5 potency in vitro, accounting for roughly 7 percent of total pharmacologic activity. CYP3A4 is the main route, with CYP3A5 and CYP2C contributing.

09Seal on the mid-start

This despatch was opened on the 5 mg lock, annotated against the vardenafil US label and the 59-man QT study, countersigned by Dr. Nora Lindqvist on 21 August 2026, and sealed with the quote card below.

GoodRx's 5 mg x 30 board ($1,093.22 retail / $125.33 coupon, 6 July 2026) is the nearest published line. This page asks the window to price eight tablets. Staxyn ODT is not that line. Juvia does not dispense. [email protected] takes label errata.

Longer clocks belong on the tadalafil 20 mg letter. Food-delay clocks belong on sildenafil 50 mg. The three-way sheet is PDE5 versus. The mid-start stays 5 mg until a countersign moves it.

Generic vardenafil 5 mg, eight tablets, the Juvia mid-start lock, August 2026. GoodRx Levitra table lists 5 mg x 30 at $1,093.22 average retail and $125.33 with a coupon (06 July 2026). Staxyn 10 mg ODT is a different fill. Juvia does not dispense.