# Vardenafil vs tadalafil: how the labels differ > Vardenafil (Levitra) and tadalafil (Cialis) are both FDA-approved PDE5 inhibitors for ED, but their labels differ most in timing. Vardenafil's half-life is about 4 to 5 hours; tadalafil's averages 17.5 hours, with effects shown up to 36 hours. A high-fat meal can lower vardenafil's peak but not tadalafil's, and their side-effect lists differ. _Last updated: 2026-10-17_ --- Status: FDA-approved prescription medicine for ED. Source: vardenafil hydrochloride prescribing information (Lannett) and Cialis prescribing information (Eli Lilly), DailyMed, checked 2026-10-17. **In short:** vardenafil (brand name Levitra) and tadalafil (brand name Cialis) work through the same enzyme and were both first approved in the US in 2003 ([vardenafil label, DailyMed](https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=2782efed-6198-47b9-81ac-3e255e2ab7f6); [Cialis label, DailyMed](https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=bcd8f8ab-81a2-4891-83db-24a0b0e25895)). On paper they are the short-acting and the long-acting ends of the class. This page sets the two FDA labels side by side, then looks at the few studies that compared them directly. **Evidence level:** both are approved drugs used for their labeled purpose, each backed by placebo-controlled trials; the head-to-head evidence cited here is one small open-label crossover study, observational data and one network meta-analysis. | Feature | Vardenafil (Levitra) | Tadalafil (Cialis) | | -------------------------------- | --------------------------------------------------------------------------------- | ------------------------------------------------------------------------------------- | | Drug class | PDE5 inhibitor | PDE5 inhibitor | | Labeled uses | Erectile dysfunction | Erectile dysfunction; signs and symptoms of BPH; both together | | Ways the label allows it | As needed only | As needed, or once daily | | Peak blood level (label) | 30 minutes to 2 hours, median 60 minutes (fasted) | 30 minutes to 6 hours, median 2 hours | | Half-life (label) | About 4 to 5 hours | Mean 17.5 hours in healthy subjects | | Window shown in trials | No fixed window on the label | Improved erectile function compared with placebo up to 36 hours after a dose | | High-fat meal | Peak level 18% to 50% lower in two food studies | No effect on the rate or extent of absorption | | Most common side effects (label) | Headache, flushing, rhinitis (runny or stuffy nose), indigestion | Headache, indigestion, back pain, muscle aches, nasal congestion, flushing, limb pain | | Warning only one label carries | QT prolongation: avoid with congenital long QT or class IA or III antiarrhythmics | Back pain and muscle aches that tend to start 12 to 24 hours after a dose | | Other forms | Orally disintegrating tablet, taken without liquid | Tablet | | Never combine with | Nitrates, riociguat | Nitrates, riociguat | Figures come from the FDA prescribing information for [vardenafil tablets](https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=2782efed-6198-47b9-81ac-3e255e2ab7f6), [vardenafil orally disintegrating tablets](https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=0ce4eb7b-fa50-441d-ae71-eb33dca27926) and [Cialis](https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=bcd8f8ab-81a2-4891-83db-24a0b0e25895). Each label reports its own trials, so the rows line up the labels; they are not a head-to-head test. ## What is the difference between vardenafil and tadalafil? The main difference is how long each one stays active: vardenafil is a short-acting pill, and tadalafil is the long-acting member of the class. Both block PDE5, the enzyme that breaks down cGMP, the messenger that relaxes blood vessels in the penis during arousal, and both labels say sexual stimulation is still needed for them to work ([vardenafil label](https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=2782efed-6198-47b9-81ac-3e255e2ab7f6); [Cialis label](https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=bcd8f8ab-81a2-4891-83db-24a0b0e25895)). Tadalafil also has two labeled uses vardenafil lacks: once-daily use for ED and treatment of the urinary symptoms of an enlarged prostate (BPH). Vardenafil, in turn, comes in a tablet that dissolves on the tongue; its label says that version is not interchangeable with the film-coated tablet ([vardenafil ODT label](https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=0ce4eb7b-fa50-441d-ae71-eb33dca27926)). ## How do they differ in how long they last? Tadalafil lasts far longer: its label reports improved erectile function compared with placebo for up to 36 hours after a dose, and a mean half-life of 17.5 hours in healthy subjects ([Cialis label](https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=bcd8f8ab-81a2-4891-83db-24a0b0e25895)). Vardenafil's label gives a half-life of about 4 to 5 hours for the drug and its main metabolite, and peak blood levels at a median of 60 minutes ([vardenafil label](https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=2782efed-6198-47b9-81ac-3e255e2ab7f6)). Tadalafil's peak comes later, at a median of 2 hours. A 2015 review of the class put vardenafil's usual duration of action at 5 to 7 hours, with a maximum of 12, against 24 to 36 hours for tadalafil, with a reported maximum of 72 ([Evans and Hill, Patient Preference and Adherence, 2015](https://pmc.ncbi.nlm.nih.gov/articles/PMC4542406/)). Our guide to [how long tadalafil lasts](/how-long-does-tadalafil-last/) covers the half-life in more depth, and [daily vs on-demand tadalafil](/daily-vs-on-demand-tadalafil/) explains the once-daily option. ## Does food affect them differently? Yes: a high-fat meal can lower vardenafil's peak blood level but does not change how tadalafil is absorbed. The Cialis label says food does not influence the rate or extent of absorption ([Cialis label](https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=bcd8f8ab-81a2-4891-83db-24a0b0e25895)). The vardenafil label says the tablet can be taken with or without food, but its two food studies found high-fat meals lowered peak blood levels by 18% to 50% ([vardenafil label](https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=2782efed-6198-47b9-81ac-3e255e2ab7f6)). For the dissolving tablet, a high-fat meal did not change total exposure or time to peak but lowered the peak by 35% ([vardenafil ODT label](https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=0ce4eb7b-fa50-441d-ae71-eb33dca27926)). ## How do the side effects compare? Both labels list the same core group of side effects, mainly headache, flushing, nasal symptoms and indigestion, but tadalafil adds back pain and muscle aches. In vardenafil's pooled placebo-controlled trials, headache was reported by 15% (placebo 4%), flushing 11%, rhinitis 9% and indigestion 4%, with a dose effect for several of them ([vardenafil label](https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=2782efed-6198-47b9-81ac-3e255e2ab7f6)). In tadalafil's as-needed trials, headache ran from 11% to 15% across the doses studied (placebo 5%), indigestion 4% to 10%, back pain 3% to 6% and muscle aches 1% to 4% ([Cialis label](https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=bcd8f8ab-81a2-4891-83db-24a0b0e25895)). The Cialis label adds that in its pharmacology trials, back pain or muscle aches generally began 12 to 24 hours after a dose and usually eased within 48 hours. In vardenafil's trials, back pain was close to placebo (2.0% against 1.7%). For the full tadalafil list, see [tadalafil side effects](/tadalafil-side-effects/). ## Which label warnings differ? The clearest difference is heart rhythm: the vardenafil label says men with congenital QT prolongation, or who take class IA antiarrhythmics such as quinidine or procainamide or class III antiarrhythmics such as amiodarone or sotalol, should avoid it ([vardenafil label, section 5.7](https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=2782efed-6198-47b9-81ac-3e255e2ab7f6)). In its own study, vardenafil raised the QTc interval about as much as the active control moxifloxacin, and a postmarketing study found the effect added up when vardenafil was combined with another drug of similar QT effect. The Cialis label reports a QT study in 90 healthy men and carries no equivalent "avoid" warning ([Cialis label](https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=bcd8f8ab-81a2-4891-83db-24a0b0e25895)). Other differences on the labels: - **Nitrates in an emergency.** Both drugs are contraindicated with nitrates. Because tadalafil lasts longer, its label says that if a nitrate is medically necessary in a life-threatening situation, at least 48 hours should have passed since the last dose, and only under close medical supervision. See [nitrates and ED medications](/nitrates-and-ed-medications/). - **Alcohol.** The Cialis label warns that substantial drinking (5 units or more) combined with tadalafil can raise the chance of dizziness, a faster heart rate and a drop in standing blood pressure. The vardenafil label reports a study in healthy volunteers in which vardenafil did not add to alcohol's blood-pressure effect over 4 hours. - **Interactions with strong CYP3A4 inhibitors.** Both labels set stricter limits with drugs such as ritonavir and ketoconazole. In one vardenafil study, ritonavir raised vardenafil exposure 49-fold and stretched its half-life to 26 hours. - **Older men.** Men 65 and older had higher blood levels of both drugs in label studies: 52% higher total exposure for vardenafil and 25% higher for tadalafil. - **Phenylalanine.** The Lannett vardenafil tablets contain aspartame, and their label carries a warning for people with phenylketonuria (PKU). Neither vardenafil nor tadalafil can be taken with nitrate heart medicines such as nitroglycerin, or with the pulmonary-hypertension drug riociguat, because the combination can drop blood pressure dangerously. Both labels tell men to stop and seek medical care for sudden loss of vision in one or both eyes or a sudden drop in hearing, and to get emergency help for an erection lasting more than 4 hours. ## Is vardenafil or tadalafil more effective? No large trial has settled it, and the evidence that exists leans toward tadalafil on satisfaction and tolerability rather than proving it works better for every man. A 2015 network meta-analysis of 82 trials (47,626 men) found that at standard starting doses tadalafil had intermediate efficacy with the lowest overall rate of side effects, while vardenafil had side-effect rates similar to sildenafil's but "markedly lower global efficacy" ([Chen et al., European Urology, 2015](https://pubmed.ncbi.nlm.nih.gov/25817916/)). Network analyses rely on indirect comparisons, so this is a ranking, not a verdict. In a small open-label crossover study at a Barcelona hospital, in which 90 men with mild to moderate ED tried sildenafil, vardenafil and tadalafil in turn, erectile function and treatment-satisfaction scores favored tadalafil over vardenafil, and 52% chose tadalafil, 28% sildenafil and 20% vardenafil; 94% said they would take another of the three if their first choice were unavailable ([Tolrà et al., Journal of Sexual Medicine, 2006](https://pubmed.ncbi.nlm.nih.gov/16942534/)). ## What do real-world studies show? In a large European observational study, men on tadalafil reported numerically higher effectiveness and satisfaction than men on vardenafil or sildenafil, but all three drugs helped. The European EDOS study followed 8,047 men at 904 sites for 6 months; 993 started on vardenafil and 5,315 on tadalafil, and the groups differed significantly in a "time concerns" measure in tadalafil's favor ([Martin-Morales et al., European Urology, 2007](https://pubmed.ncbi.nlm.nih.gov/17084518/)). Men chose their own drug in this study, so it cannot show cause and effect. A review describing the same data noted that at least 90% of men on vardenafil or sildenafil reported that the longest gap between a dose and successful intercourse was about 12 hours or less, against 48 hours or less for 90% of men on tadalafil ([Evans and Hill, 2015](https://pmc.ncbi.nlm.nih.gov/articles/PMC4542406/)). The same review summarized a Japanese survey in which neither vardenafil nor tadalafil scored significantly better than the other on self-confidence or spontaneity, and tadalafil scored lower than vardenafil or sildenafil on time concerns, the opposite of the EDOS finding. ## When should you talk to a clinician about switching? Talk to a clinician before starting either one, and again if the first pill caused side effects you dislike or did not work well enough, because both are prescription medicines and the right choice depends on your health and other medicines. The American Urological Association says men with ED "should be informed regarding the treatment option of an FDA-approved oral phosphodiesterase type 5 inhibitor (PDE5i), including discussion of benefits and risks/burdens, unless contraindicated," and that ED is a risk marker for underlying cardiovascular disease ([AUA Erectile Dysfunction guideline]()). Bring a full list of medicines, especially heart-rhythm drugs, nitrates, alpha-blockers, antifungals, antibiotics and HIV medicines, and mention any heart, eye, liver or kidney history. A man born with long QT syndrome has a label-based reason to avoid vardenafil, and back pain or muscle aches on tadalafil are worth raising with the prescriber. Which pill fits, and how to take it, is a decision for you and the prescriber. For the other pairings, see [vardenafil vs sildenafil](/vardenafil-vs-sildenafil/) and [tadalafil vs sildenafil](/tadalafil-vs-sildenafil/). ## Sources 1. [Vardenafil hydrochloride tablets, prescribing information, Lannett Company, DailyMed](https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=2782efed-6198-47b9-81ac-3e255e2ab7f6) 2. [Vardenafil hydrochloride orally disintegrating tablets, prescribing information, Alembic Pharmaceuticals, DailyMed](https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=0ce4eb7b-fa50-441d-ae71-eb33dca27926) 3. [Cialis (tadalafil) tablets, prescribing information, Eli Lilly, DailyMed](https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=bcd8f8ab-81a2-4891-83db-24a0b0e25895) 4. [Chen L et al. Phosphodiesterase 5 inhibitors for the treatment of erectile dysfunction: a trade-off network meta-analysis. European Urology, 2015](https://pubmed.ncbi.nlm.nih.gov/25817916/) 5. [Tolrà JR et al. Prospective, randomized, open-label, fixed-dose, crossover study to establish preference of patients with erectile dysfunction after taking the three PDE-5 inhibitors. Journal of Sexual Medicine, 2006](https://pubmed.ncbi.nlm.nih.gov/16942534/) 6. [Martin-Morales A et al. Therapeutic effectiveness and patient satisfaction after 6 months of treatment with tadalafil, sildenafil, and vardenafil: results from the erectile dysfunction observational study (EDOS). European Urology, 2007](https://pubmed.ncbi.nlm.nih.gov/17084518/) 7. [Evans JD, Hill SR. A comparison of the available phosphodiesterase-5 inhibitors in the treatment of erectile dysfunction: a focus on avanafil. Patient Preference and Adherence, 2015](https://pmc.ncbi.nlm.nih.gov/articles/PMC4542406/) 8. [Erectile Dysfunction: AUA Guideline, American Urological Association]() --- _Affiliate disclosure: some links on the web version of this site go to Bodybuilding Peptides (trybbpeptides.com), an affiliate destination, and we may earn a commission if you buy there. Our coverage is independent of that relationship. Details: https://theedreport.com/affiliate-disclosure/_