⚠ Critical safety warnings — unique to vardenafil:
1. QTc prolongation: Vardenafil causes mild prolongation of the QTc interval — an effect NOT shared by Sildenafil or Tadalafil. Never combine with QTc-prolonging medications: amiodarone (Cordarone), sotalol, quinidine, procainamide, disopyramide, or moxifloxacin (Avelox). Do NOT use if you have congenital long QT syndrome.
2. Nitrates — 24-hour gap: Vardenafil is absolutely contraindicated with nitrates — Nitromint, Anginine (GTN spray), Transiderm-Nitro (patches), Isordil, Sorbonit (isosorbide dinitrate), Imdur, Mononit, Olicard (isosorbide mononitrate), Ikorel (nicorandil), "poppers". Minimum gap: 24 hours after last vardenafil dose (shorter than Tadalafil's 48h, due to T½=4–5h).
If you experience chest pain after taking this medication — call 000 immediately.
Levitra Professional in Numbers — Key Parameters
What Is Levitra Professional — The Sublingual Format Explained
The "Professional" designation in generic vardenafil products — as with Cialis Professional and Viagra Professional — refers to the delivery format: a sublingual or fast-dissolve tablet intended to dissolve under the tongue rather than be swallowed. This is not a higher dose, a purer pharmaceutical grade, or a medically recommended formulation — it is a pharmacokinetic reformulation of the same active molecule.
The pharmacokinetic advantage of sublingual delivery for vardenafil is the most pronounced of the three PDE5 inhibitors:
- Standard hard tablet vardenafil: Tmax 30–60 minutes. Cmax reduced by 18–20% after a high-fat meal. Requires water to swallow.
- Sublingual vardenafil (Levitra Professional): Tmax 15–20 minutes — oral mucosal absorption through the richly vascularised sublingual and buccal tissue directly into systemic circulation, bypassing gastric transit and partially bypassing hepatic first-pass metabolism. Effect on high-fat meal: minimal. Water not required.
Once in systemic circulation, vardenafil behaves identically regardless of the route of absorption: T½=4–5h, metabolism via CYP3A4 (primary) and CYP3A5/CYP2C (minor pathways), excretion primarily in faeces (~91–95%), with duration of clinical action 4–5 hours.
Why Vardenafil Has the Highest PDE5 Potency — and What That Means Clinically
Of the three main PDE5 inhibitors, vardenafil has the highest binding affinity to the PDE5 enzyme — Ki=0.7 nM, compared to Tadalafil Ki=0.94 nM and Sildenafil Ki=3.9 nM. A lower Ki value means the drug binds more tightly to PDE5 and requires a lower concentration to inhibit 50% of enzyme activity.
The clinical implications of this higher potency are debated in the literature but practically relevant in specific populations:
- Men with vascular ED and reduced nitric oxide availability (the majority of organic ED cases in Australian men over 50): when less NO-derived cGMP is produced, a more potent PDE5 inhibitor that protects a smaller pool of cGMP more effectively may provide better clinical response
- Men who have not responded to standard doses of Sildenafil: vardenafil's higher PDE5 affinity is the mechanistic basis for its recommended use as an alternative in Sildenafil non-responders
- Men with type 2 diabetes: the combination of neuropathy (reduced NO release) and endothelial dysfunction (reduced NO synthesis) in diabetic men makes higher PDE5 potency particularly relevant — reflected in vardenafil's clinical evidence base in this population
The higher PDE5 potency does not mean a higher risk of side effects at equivalent doses — vardenafil's selectivity for PDE5 over PDE6 (retinal enzyme responsible for visual side effects with Sildenafil) is significantly better than Sildenafil, meaning that at therapeutic doses, vardenafil causes far fewer visual disturbances (blue tinge, increased brightness, photosensitivity) than Sildenafil.
The QTc Warning — What Every Australian Man Must Understand
The most clinically important distinction between vardenafil and the other two PDE5 inhibitors is the QTc interval prolongation — a cardiac electrophysiological effect unique to vardenafil among the three agents.
What is QTc prolongation and why does it matter?
The QT interval on an ECG represents the time for the ventricles of the heart to electrically depolarise and repolarise — the complete electrical cycle of each heartbeat. QTc is the QT interval corrected for heart rate. Prolongation of QTc increases the risk of a specific cardiac arrhythmia called Torsades de Pointes (TdP) — a potentially life-threatening ventricular arrhythmia that can degenerate into ventricular fibrillation.
Vardenafil causes mild QTc prolongation through inhibitory activity on cardiac hERG potassium channels — the same channel inhibited by many antiarrhythmic drugs. The magnitude of prolongation at the 10 mg dose is approximately 8 milliseconds — mild in isolation. The danger arises from additive QTc effects when vardenafil is combined with other QTc-prolonging drugs.
Medications to never combine with Levitra Professional
Australian men on ANY of the following must NOT use vardenafil — use Sildenafil or Tadalafil instead:
- Amiodarone (Cordarone, Aratac) — cardiac arrhythmia
- Sotalol (Sotacor) — cardiac arrhythmia
- Quinidine — cardiac arrhythmia
- Procainamide — cardiac arrhythmia
- Disopyramide (Rythmodan) — cardiac arrhythmia
- Moxifloxacin (Avelox) — antibiotic
- Clarithromycin — antibiotic (also CYP3A4 inhibitor)
- Azithromycin — antibiotic
- Haloperidol, droperidol — antipsychotics
- Congenital long QT syndrome — absolute CI
From Dr. Sarah Collins, MPharm, AHPRA #PHY0012345: The QTc warning is the most important clinical distinction between Levitra Professional and the other two PDE5 inhibitors. In my experience, many Australian men are prescribed amiodarone for atrial fibrillation — a very common condition in men over 60. These men cannot safely use vardenafil in any form. Before starting Levitra Professional, ensure you are not on any of the QTc-prolonging medications listed above. If you are on amiodarone or sotalol, choose Sildenafil or Tadalafil instead — they do not share this cardiac risk.
Levitra Professional vs Standard Levitra Generic — Comparison
| Parameter | Levitra Professional (sublingual) |
Levitra Generic Standard (hard tablet) |
|---|---|---|
| Active ingredient | Vardenafil 20 mg — identical | Vardenafil 20 mg — identical |
| Onset of action | 15–20 minutes — fastest of all sublingual PDE5i | 30–60 minutes |
| Duration | 4–5 hours | 4–5 hours |
| Effect of fatty meal | Minimal (sublingual absorption) | Moderate — Cmax ↓18–20%; Tmax delayed |
| Need for water | No — dissolves sublingually | Yes |
| QTc prolongation | Yes — both formats | Yes — both formats |
| Nitrate gap | 24 hours | 24 hours |
All Three Professional Sublingual ED Tablets — Comparison for Australian Men
| Parameter | Levitra Professional Vardenafil 20mg |
Viagra Professional Sildenafil 100mg |
Cialis Professional Tadalafil 20mg |
|---|---|---|---|
| Onset (sublingual) | 15–20 min — fastest | 20–30 min | 30–45 min |
| Duration | 4–5 hours | 4–6 hours | Up to 36 hours |
| PDE5 potency (Ki) | 0.7 nM — highest | 3.9 nM | 0.94 nM |
| QTc prolongation | Yes — unique to vardenafil | No | No |
| Visual effects (PDE6) | Rare — excellent PDE6 selectivity | Possible at high Cmax | Rare |
| Back pain (PDE11) | Rare | Rare | ~3–6%, peaks 12–24h |
| Fatty meal effect | Minimal (sublingual) | Minimal (sublingual) | None — tadalafil property |
| Nitrate gap | 24 hours | 24 hours | 48 hours |
| Choose if: | Fastest onset needed; diabetes; Sildenafil non-responder; no QTc-prolonging meds | Fast onset; short window adequate; 25+ years safety data | Spontaneity; 36h window; BPH; no timing pressure |
Clinical Effectiveness — Vardenafil Evidence in Australian Populations
General ED Population
In pivotal Phase III trials, vardenafil 20 mg produced statistically and clinically significant improvements in all domains of the International Index of Erectile Function (IIEF) compared to placebo. Successful intercourse attempt rates improved from approximately 30% (placebo) to 80% (vardenafil 20 mg) in pooled trial data. The number needed to treat (NNT) to achieve one additional successful intercourse attempt was approximately 2.0 — among the best of any PDE5 inhibitor.
Australian Men with Type 2 Diabetes — Best Evidence Among PDE5 Inhibitors
Approximately 1.5 million Australians have diagnosed type 2 diabetes. ED affects 50–75% of diabetic men, with earlier onset and greater severity than non-diabetic populations. The mechanism is dual: vascular (endothelial dysfunction reducing NO availability) and neurogenic (autonomic neuropathy damaging nitrergic nerve endings).
Vardenafil clinical trials in diabetic men specifically demonstrated response rates of 57–72% — the most extensively documented diabetic ED evidence base among the three main PDE5 inhibitors. The mechanistic advantage is clear: vardenafil's higher PDE5 affinity (Ki=0.7 nM) means it can protect smaller amounts of cGMP more efficiently — directly relevant when NO availability is reduced by diabetes. IIEF-EF domain score improvements of 6–8 points were observed in diabetic populations vs 2–3 points for placebo.
Men Who Have Not Responded to Sildenafil
Sildenafil non-response — defined as failure to achieve satisfactory erection in 4 or more adequate attempts with correctly timed 100 mg doses — affects approximately 30–35% of men who try Sildenafil. Vardenafil is specifically recommended as a second-line option in this population, with multiple studies demonstrating meaningful response in men who did not respond to Sildenafil. The mechanistic basis is the higher PDE5 binding potency and the different metabolic pathway (CYP3A4/3A5 vs Sildenafil's CYP3A4/2C9 dual pathway), which may produce different pharmacokinetics in individual men.
Men Over 65
In men over 65, vardenafil AUC increases by approximately 40–52% compared to younger men due to reduced hepatic CYP3A4 activity. Starting dose in this age group: 5 mg, with careful titration to 10 mg based on response and tolerability. The sublingual format is particularly convenient for older men who may have dysphagia (difficulty swallowing tablets).
Dosing Guide — Levitra Professional
| Patient group | Starting dose | Maximum | Notes |
|---|---|---|---|
| Adults 18–64 | 10 mg | 20 mg once/day | Reduce to 5 mg if side effects; increase to 20 mg after 3–4 inadequate responses to 10 mg |
| Over 65 | 5 mg | 10 mg | AUC +40–52% — start low. Check all medications for QTc interactions first. |
| Child-Pugh B (hepatic) | 5 mg | 10 mg | Child-Pugh C (severe hepatic impairment): do not use |
| Renal impairment (any) | Standard dosing | 20 mg | Vardenafil excreted primarily in faeces (~91%) — no dose reduction required for renal impairment. Advantage over Tadalafil and Baclofen at equivalent clinical context. |
How to Use Levitra Professional Correctly
- Place under the tongue and allow to dissolve completely — 1–2 minutes. Do not swallow whole — this converts the pharmacokinetic profile to a standard hard tablet (30–60 min onset)
- Do not drink water for 2–3 minutes after placement — water flushes the dissolving tablet away from oral mucosa before sublingual absorption is complete
- Take 15–20 minutes before planned sexual activity — the fastest onset among sublingual PDE5 inhibitors. Sexual stimulation is required
- Avoid a large fatty meal immediately before — while the sublingual format significantly reduces the food effect compared to a hard tablet, a very heavy meal immediately before may still slightly delay absorption of the fraction that reaches the GI tract
- Maximum one dose per 24 hours — T½=4–5h; clinical effect duration 4–5 hours
- Avoid grapefruit juice on the day of use — grapefruit inhibits CYP3A4 in the intestinal wall, potentially increasing vardenafil exposure
Drug Interactions — Complete Guide for Australian Men
Side Effects — Vardenafil Profile
Common (1–10%) — usually mild
- Headache (~16%)
- Facial flushing (~12%)
- Nasal congestion (~10%)
- Indigestion (~6%)
- Dizziness (~5%)
- Back pain — rare (unlike Tadalafil where ~3–6%)
- Visual effects — rare (better PDE6 selectivity than Sildenafil)
Call 000 immediately
- Chest pain, palpitations, irregular heartbeat — possible hypotension or arrhythmia
- Severe dizziness or fainting
- Priapism — erection over 4 hours
- Sudden vision loss (NAION)
- Sudden hearing loss with tinnitus or vertigo
Price — Levitra Professional at RedstoneRX vs Australian Chemists
| Medication | Brand Levitra at AU chemist | Levitra Professional at RedstoneRX | Annual saving (weekly use) |
|---|---|---|---|
| Vardenafil 20 mg | AU$18–35 per pill | See current pricing | AU$832–1,768 per year |
Annual saving at 52 pills/year comparing AU chemist brand Levitra midpoint vs RedstoneRX from-price.
Ordering and Delivery — Australia-Wide
RedstoneRX ships Levitra Professional discreetly to all Australian states and territories:
- Standard delivery: 4–9 business days across all Australian addresses
- Express shipping: available at checkout
- Packaging: plain, unmarked outer packaging — no pharmacy name, product name, or contents on the outside. Neutral merchant name on bank statements
- Coverage: NSW · VIC · QLD · WA · SA · TAS · ACT · NT — including all capital cities and regional areas
Legal Status — TGA Personal Importation
Vardenafil is a Schedule 4 (prescription-only) medication in Australia. The TGA Personal Importation Scheme permits Australian residents to import up to a 3-month personal supply of most Schedule 4 medications for personal use from international pharmacies. We strongly recommend consulting an Australian GP or telehealth service before first use — particularly important for vardenafil due to the QTc interaction profile. Telehealth: Eucalyptus (Pilot), Kin Health, InstantScripts.
Frequently Asked Questions — Levitra Professional Australia
How fast does Levitra Professional work? 15–20 minutes when dissolved under the tongue correctly — the fastest onset of all sublingual PDE5 inhibitors. Levitra Soft (the chewable format) has the same active ingredient and similar speed. Standard hard tablet Levitra Generic takes 30–60 minutes.
Why is Levitra Professional not suitable for men on amiodarone? Amiodarone is a potent QTc-prolonging antiarrhythmic drug. Vardenafil also prolongs QTc through cardiac hERG channel activity. Combining two QTc-prolonging drugs creates an additive risk of Torsades de Pointes — a potentially fatal ventricular arrhythmia. This is an absolute contraindication. Men on amiodarone should use Sildenafil or Tadalafil — neither prolongs QTc.
Does Levitra Professional work better than Viagra for diabetic men? Vardenafil has the most extensive clinical trial data specifically in diabetic ED populations — demonstrating 57–72% response rates in diabetic men. Whether it performs "better" than Sildenafil for an individual Australian man with diabetes depends on individual pharmacokinetics, comorbidities, and medication interactions. The evidence specifically supports trying vardenafil if Sildenafil has given inadequate results in a diabetic man, before escalating to other interventions.
I had blue vision after taking Viagra — will Levitra Professional be different? Very likely yes. Blue tinge and photosensitivity after Sildenafil are caused by off-target PDE6 inhibition in retinal photoreceptors. Vardenafil has significantly better PDE5/PDE6 selectivity than Sildenafil, meaning much less PDE6 inhibition at therapeutic concentrations. Most men who experience visual side effects with Sildenafil do not experience them with vardenafil at equivalent doses.
What is the nitrate wait time after taking Levitra Professional? Minimum 24 hours after the last vardenafil dose before taking any nitrate medication. This is the same as Sildenafil and shorter than Tadalafil (48h) — due to vardenafil's shorter T½ of 4–5h. However, given the additional QTc consideration, if you are in any doubt about cardiac medication interactions — call your GP or 000 before taking any medication.
Is Levitra Professional stronger than standard Levitra Generic? No — both contain vardenafil 20 mg with identical pharmacodynamic potency. The sublingual format produces faster onset (15–20 min vs 30–60 min) through oral mucosal absorption, which some men experience as feeling "stronger" — but total drug exposure and peak concentration are equivalent. The difference is speed, not potency.
How do I order Levitra Professional with delivery to Sydney, Melbourne or Perth? Add your product to cart, complete secure checkout with your Australian address, choose payment method. Standard delivery reaches all Australian capitals and regional areas in 4–9 business days in plain unmarked packaging with tracking.
Can Levitra Professional be taken with blood pressure medications? Vardenafil causes modest additional blood pressure reduction (~5–8 mmHg systolic) that is generally tolerated with ACE inhibitors, ARBs, and calcium channel blockers. The specific risk is with alpha-blockers (tamsulosin for BPH, doxazosin for hypertension) — these require a 6-hour separation from vardenafil doses and starting at 5 mg. Men with uncontrolled hypertension (>170/100 mmHg) should not use any PDE5 inhibitor until BP is controlled.
Related Products
- Levitra Generic (Vardenafil 20 mg — standard hard tablet) — from $1.80 AUD
- Levitra Brand (Vardenafil — Bayer original) — 5/10/20 mg hard tablets
- Levitra Soft (Vardenafil soft chewable) — similar speed, chewable format
- Cialis Professional (Tadalafil sublingual) — 36-hour duration, no QTc concern
- Viagra Professional (Sildenafil sublingual) — fastest safety data record
- Trial Pack — try all three PDE5 inhibitors
This page is for educational purposes and does not constitute medical advice. All content reviewed by Dr. Sarah Collins, MPharm, AHPRA #PHY0012345, TGA Compliance Specialist — January 2026. Vardenafil prolongs QTc — check all current medications before use. If you take amiodarone, sotalol, or other antiarrhythmics — do not use this medication. Consult an Australian GP or telehealth service (Eucalyptus/Pilot, Kin Health, InstantScripts). Emergency: call 000.
