Which of the three is strongest?
Three clocks, three locked milligrams
Lay the three filed milligrams on one parchment. Cialis 20 mg once is a PRN almond with a long tail, not a breakfast strip. Viagra 100 mg is a late diamond on an empty plate. Levitra 2.5 or 10 is an opener pair with a QT tick, not a 20 mg trophy.
None of those locks is a starter-for-everyone stamp. The labels still run their own ladders: tadalafil 10 mg PRN typical start and 2.5/5 daily; sildenafil 50 mg typical start; vardenafil 10 mg typical start. This site chose different rungs so the network does not reprint one postcard. Peel the lock. Then score the man.
This page does not rerun three monographs. It only asks how the three clocks differ once the milligrams are nailed down. For lane detail see daily versus the almond. For the Sandwich miss see the origin slip. For the QT footnote see the selectivity file.
Nitrate washouts are not twins
Nitrate washouts are not twins. The contraindication is identical: no nitrate, no popper, no riociguat, with any of the three. The clocks differ because clearance differs. After sildenafil or vardenafil, plan about 24 hours. After tadalafil, plan about 48 hours.
A longer gap is not a nastier drug. It is a longer presence in blood. Emergency teams need the INN and the hour, not 'I take something for sex.' Men who live with a nitrate spray do not get a comparison - they get a closed class.
Alpha-blockers are sequenced cautions on all three, not twins of the nitrate ban. CYP3A4 inhibitors raise all three and shrink starting doses. The holds look similar until you put the clocks on the parchment. Then tadalafil's extra day is the line residents forget.
How this bench actually chooses among the three
How this bench actually chooses among the three starts with holds, not with a crown. Nitrate life? Class closed. Dirty QT or amiodarone? Drop vardenafil. Fatty dinners that will not move? Prefer tadalafil. Need a prostate chip as well? Tadalafil 5 mg daily, not a 20 mg stack.
Want a weekend from one swallow? 10 or 20 mg tadalafil PRN - this desk's lock is 20 once after a real 10 mg trial. Want a punctual evening and an empty-enough plate? Sildenafil, and remember 100 mg is the late diamond. Want a small tablet, clean ECG, short clock? Vardenafil 10 mg, or 2.5 mg when the interaction list demands it.
Still no erection after an honest trial? Stop comparing milligrams. Open the failure workup. A PDE5 slip is one tool. Three clocks on one parchment do not replace a vascular, nerve, hormone, or mood file.
Link the three labels before you pick a clock. The tadalafil slip owns the long tail and the prostate chip. The sildenafil slip owns the empty plate and the late diamond. The vardenafil slip owns the QT tick and the 2.5-or-10 opener. That is the whole comparison once the holds are peeled.
Fat punishes two slips and ignores one
| Locked slip | Clock | Food | Extra ink |
|---|---|---|---|
| Cialis 20 mg once | Peak ~2 h; tail up to ~36 h | Quiet | Daily 2.5/5 is another lane - do not stack |
| Viagra 100 mg | Peak ~1 h; ~4 h cover | High-fat: Cmax -29%, Tmax +~60 min | Revatio is another product |
| Levitra 2.5 or 10 | Peak ~0.5-2 h; short evening | Heavy meal can blunt | QT tick; Staxyn not a twin |
Fat punishes two slips and ignores one. Sildenafil's high-fat meal story is the sharpest: about 29 percent less Cmax and about an hour of delay. Vardenafil's film coat still blunts after a heavy plate. Tadalafil's food line is quiet - almond or chip, steak or not.
If the couple's life is dinner-then-bed and they will not move the meal, the 20 mg almond (or a daily 5 mg chip already at steady state) is the honest food pick. Escalating Viagra 100 mg to overpower a steak is how you meet PDE6 and a headache.
Empty plate is a sildenafil counseling stamp on this desk, not a moral rule. A quieter stomach is enough. Nobody needs to skip eating. They need to stop running a bioavailability trial against cream sauce.
Who peaks first on an emptier stomach
Who peaks first on an emptier stomach? Sildenafil and vardenafil share a short-clock family: Tmax often inside 30 to 120 minutes, median nearer an hour when the plate is quiet. Tadalafil's peak sits nearer two hours, then refuses to leave.
So the man who wants an evening that starts soon, and who can keep the richest course away from the tablet, may find the diamond or the 10 mg Levitra film coat more punctual. The man who wants Friday's swallow to still matter on Sunday morning wants the almond, and he can wait the extra bit to peak.
Onset is not potency. A faster peak is not a harder erection. It is a clock. I get more false failures from people who swallowed at the wrong hour than from people who picked the 'weaker' INN.
Stimulation still has to be in the room for all three. A punctual peak on an empty sofa is a quiet tablet, not a broken molecule. I would rather move the hour than swap INNs because someone sat through the Tmax window scrolling a phone.
Weekend versus an evening
Weekend versus an evening is the span question. Tadalafil's 17.5-hour half-life is why one 20 mg almond can still support a response the next day. Sildenafil and vardenafil live nearer four to five hours. Their honest promise is an evening, not a Sunday morning.
Daily tadalafil 2.5 or 5 mg is a fourth clock that only one molecule owns. It is not in the 20 mg lock. It is in the lane review. Do not put a breakfast chip in this comparison as if it were a fourth INN.
Men who have sex twice a month usually waste a daily chip. Men who refuse any countdown often waste a short-clock tablet. Match the span to the life. Do not match it to a crown.
Back ache after tadalafil is a class-adjacent nuisance some men notice more on the long molecule. Flush and headache show up on all three. I do not switch INNs for a mild flush that faded. I do switch when a nuisance is the reason the man will not take the next honest trial.
Price talk here is teaching, not a shop
Price talk here is teaching, not a shop. This desk does not invent a dollar or point at a hatch. The lesson is calendar maths. A daily 2.5 or 5 mg chip costs a tablet on days nobody has sex. A 20 mg almond costs when you open the bottle. A 100 mg diamond and a 10 mg Levitra do the same: pay per event.
Rare sex plus a daily chip is how people overpay in habit even when the pharmacy number looks 'small.' Frequent unplanned sex plus a short-clock tablet is how people overpay in mood - the countdown becomes the price. I would rather a couple name that trade than hunt a fictional bargain.
Generics exist for all three INNs in many markets. Brand names on this page are teaching labels. They are not a shopping list. If someone quotes you a number, ask which milligram, which count, and which date. This parchment will not invent one.
Only one slip carries a QT tick
Only one slip carries a QT tick. Vardenafil's label warns about QT prolongation and tells you to avoid congenital long-QT and Class IA or III antiarrhythmics. Sildenafil and tadalafil do not wear that same footnote. That single line can decide the whole comparison.
Selectivity over PDE6 runs the other way as a comfort story: tadalafil almost none, vardenafil middling, sildenafil the leakiest. Blue edges are annoying. A torsades risk is a different severity. Do not let a retina story outrank an ECG story.
If the rhythm file is dirty, I drop Levitra first, even at 2.5 mg. Selectivity will not rescue that chart. See the selectivity deep-dive for the footnote in full.
None of the three is crowned on this parchment
None of the three is crowned on this parchment. File Cialis 20 mg once as a long PRN almond, Viagra 100 mg as a late empty-plate diamond, and Levitra 2.5 or 10 as a cautious short clock with a QT tick.
Food punishes two and ignores one. Nitrate gaps run 24 versus 48 hours. Only vardenafil carries the QT footnote. Cost is a calendar, not a shop. Staxyn and Revatio stay in other drawers.
Read the three labels, then the three single-molecule dives, then decide whether a tablet belongs at all. A comparison that ends with a crown is marketing. This one ends with a flat file.
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What readers wanted to know
Answered by Dr. Lena Vermeer, MD · Internal medicine & clinical pharmacology
People want me to pick a winner among the three locks. I pick a clock and a hold instead. Teaching only - Lena Vermeer.
None in the way that sentence wants. Head-to-head, the class helps in the same broad range when the man, the plate, and the clock match. Vardenafil looks 'stronger' in a test tube because it binds PDE5 at a lower concentration - that is why the milligrams are small, not why the erection is harder. This desk locked different rungs - 20 mg once, 100 mg, 2.5 or 10 - so a title would not reprint one postcard. Those locks are not a ranking. I choose by food, span, QT, and nitrates. Strength talk is how people request a trophy swallow on night one.
We eat late and heavy. Which slip even makes sense?
Tadalafil. Fat is clinically quiet on that molecule, whether the file is a 20 mg almond or a 2.5/5 mg chip. Sildenafil's high-fat meal can cut Cmax by about 29 percent and delay the peak about an hour - that is the empty-plate stamp beside the 100 mg diamond. Vardenafil's film coat still blunts after a cream sauce. If dinner will not move, I do not escalate Viagra to overpower the steak. I change the slip. Daily tadalafil is a separate lane if they also hate any countdown. Do not stack the almond on the chip to 'cover dinner.'
He is on sotalol. Which of the three can we even discuss?
Not vardenafil. Sotalol is a Class III agent, and Levitra's label tells you to avoid that pairing because QT effects add. Sildenafil and tadalafil do not wear that same footnote, so the conversation, if the cardiologist still wants a PDE5 inhibitor after nitrates and plumbing are cleared, sits on those two. Then we pick a clock: evening diamond on an emptier plate, or a long almond. 2.5 mg Levitra is not a loophole. A 'small' dose does not erase a labeled avoid. I would rather lose the selectivity story than keep a QT tick on an antiarrhythmic chart.
We want Saturday morning after a Friday tablet. Which lock is that?
The Cialis 20 mg once lock - the PRN almond, not the breakfast chip. A 17.5-hour half-life is why one swallow can still support a response the next calendar day. Viagra 100 mg and Levitra 10 mg are evening clocks. Swallowing a second short-acting tablet at midnight is not how you invent a weekend; it is how you break the once-a-day ceiling. If they also want no countdown at all, that is the daily 2.5 or 5 mg tadalafil lane, which is a different file - see the lane review. Do not run both.
Is the 100 mg Viagra 'more drug' than 20 mg Cialis?
Milligrams are not a common currency across INNs. One hundred milligrams of sildenafil is the high labeled ED tablet for that molecule. Twenty milligrams of tadalafil is the high labeled PRN tablet for that one. Ten milligrams of vardenafil is a usual start, and 20 mg is its own ceiling. Comparing 100 to 20 as if they were weights on one scale is how people request a trophy. Exposure, half-life, and food effect do the real work. I would rather you ask which clock you need than which number looks bigger on a packet.
Can we switch between the three from weekend to weekend?
You can change files. You should not stack them on one clock. Each agent has a once-a-day ceiling and a nitrate gap. Mixing a Friday almond with a Saturday diamond is how washouts get muddy and how side effects add. If you switch, pick a lane, give it an honest trial - several attempts, right plate, real arousal - then change with the prescriber, not with leftover tablets from a drawer. Revatio and Staxyn stay out of that drawer. They are other products. A comparison page is not a tasting menu.
Which one is cheapest?
I will not invent a price. What I will teach is the calendar. A daily tadalafil chip spends a tablet on quiet days. A per-event almond, diamond, or 10 mg Levitra spends when you open the bottle. Rare sex plus a daily habit is usually the expensive pattern in tablets-per-month even when each chip looks small. Frequent sex plus a short-clock tablet can be cheap in tablets and expensive in mood because of the countdown. Ask a pharmacist for today's number on a named milligram and count. This parchment stays a lesson, not a hatch.
He gets a blue tint on Viagra. Do we move to Levitra or Cialis?
Cialis is the cleaner retinal move. Tadalafil barely touches PDE6. Vardenafil is more than 15-fold selective for PDE5 over PDE6 - better than sildenafil, not a tadalafil retina - so some men still see a wash. If the tint is brief and fades, it is the known leak, not a sudden-loss emergency. Sudden loss is stop-and-go-now. I also ask whether the sildenafil trial was on a heavy plate; a delayed high peak is a good way to meet PDE6. Fix the plate before you crown a switch. Then, if the wash still bothers him, I talk tadalafil first, Levitra second.
If none is crowned, why does this site lock three different milligrams?
So the network does not reprint one postcard on every domain. Cialis 20 mg once, Viagra 100 mg, Levitra 2.5 or 10 are this desk's SERP rungs - high PRN almond, late diamond, cautious opener pair. Other sites in a teaching network may lock 5 mg daily, 50 mg, or 20 mg Levitra. The labels still contain the full ladders. I peel a lock as publishing, then I score the man on the labeled start that fits his age, liver, CYP list, and last trial. A title is not a swallow order. That is the whole point of keeping three clocks flat on one parchment.
Take each reply as a general teaching point, not a plan built for whoever asked it. Your own case - notes, bloods, every medicine you take - belongs in front of a prescriber who can weigh all of it at once.