Vega Extra Cobra (Sildenafil Citrate): Comprehensive Patient Information for Australia
Basic Product Information
| International Non-Proprietary Name (INN) | Sildenafil Citrate |
|---|---|
| Australian Brand Names | Vega Extra Cobra (not registered in Australia), Viagra, Sildegra, Vedafil, APO-Sildenafil, Sildamax |
| ATC Code | G04BE03 |
| Strengths & Forms | Tablets: 50 mg, 100 mg; non-Australian imports may be available at 120 mg or 200 mg (not TGA approved) |
| Manufacturers | Vega Extra Cobra is manufactured by various companies in India and distributed globally. Australian approved products are mostly supplied by Pfizer, Apotex, and other TGA-certified manufacturers. |
| Prescription Status | Prescription Only Medicine (Schedule 4, S4) – must be supplied and dispensed by a registered pharmacist upon valid prescription in Australia. |
Mechanism of Action
For Patients: Sildenafil Citrate (the active ingredient in Vega Extra Cobra) works by improving blood flow to the penis, which helps men achieve and maintain an erection when sexually aroused. It does not increase sexual desire and will only work with sexual stimulation.
For Healthcare Professionals: Sildenafil is a selective inhibitor of cyclic guanosine monophosphate (cGMP)-specific phosphodiesterase type 5 (PDE5). By blocking PDE5, sildenafil increases cGMP levels in the corpus cavernosum, enhancing smooth muscle relaxation and blood inflow upon sexual stimulation.
Pharmacokinetics
- Absorption: Well absorbed orally, peak plasma concentrations within 30–120 minutes (median ~60 minutes).
- Bioavailability: Approximately 41% (variable).
- Metabolism: Extensively metabolised in the liver by CYP3A4 (major route) and CYP2C9 (minor).
- Elimination: Half-life is 3–5 hours. Metabolites excreted mainly as metabolites in faeces and urine.
- Duration of Action: Effects usually last up to 4–6 hours; some effect may persist up to 12 hours in sensitive individuals.
Everyday Use & Best Practices in Australia
Typical Adult Dose: 50 mg taken approximately one hour before sexual activity, with or without food. Depending on effectiveness and tolerability, dosage may be increased to a maximum of 100 mg or decreased to 25 mg. Do not take more than one dose per day.
How to Use: Swallow the whole tablet with water. Only use Vega Extra Cobra (or Australian registered sildenafil brands) as prescribed by your doctor. Never take more than the recommended dose and avoid sharing your medication with others.
English-Australian Context: The medicine is commonly prescribed for men with proven erectile dysfunction (ED), including those experiencing ED due to diabetes, cardiovascular disease, or after prostate surgery. Regular reviews with your GP are recommended to monitor effectiveness and safety.
Morning vs Evening Dosing
- Morning: Less common, but may be suitable for men who are most sexually active in the morning. May coincide with natural testosterone peaks but also increases likelihood of interference with heavy breakfasts (see food interactions below).
- Evening: Most commonly taken 30–60 minutes before anticipated sexual activity, often in the evening. Risk of tiredness from alcohol or late meals must be considered.
- Tips: Try to take at a similar time relative to sexual activity to maintain routine and efficacy.
Taking with Food or on an Empty Stomach
Main Advice: Viagra and related sildenafil medicines work best on an empty stomach. Taking after a heavy or high-fat meal (e.g., steak, fish & chips, English breakfast) may delay onset by up to 1 hour and reduce effectiveness. Light meals are less likely to interfere.
Australian Dietary Habits: If you enjoy a large dinner or take-away before intimacy, consider waiting at least 2 hours before taking your dose, or opt for a lighter meal.
Interaction Warnings
| Interacting Agent | Interaction | Advice |
|---|---|---|
| Nitrates (e.g., glyceryl trinitrate, isosorbide mononitrate) | Severe, potentially fatal drop in blood pressure | Never use sildenafil with nitrates |
| Alpha-blockers (e.g., prazosin, tamsulosin) | Additive hypotensive effects | Stabilise on alpha-blocker before starting; monitor BP closely |
| CYP3A4 inhibitors (e.g., ketoconazole, erythromycin) | Raised sildenafil levels/increased side effects risk | May require dose reduction or avoidance |
| Alcohol | Worsened side effects, risk of fainting, reduced efficacy | Limit or avoid alcohol on days of use |
| Grapefruit juice | Can raise sildenafil levels, increasing side effects | Avoid grapefruit products while using |
| Other ED drugs (e.g., tadalafil, vardenafil) | Risk of additive side effects | Do not combine with other ED medicines |
| Recreational drugs ("poppers", amyl nitrite) | Life-threatening hypotension | Never mix with sildenafil |
Indications
| Official (Australia TGA-approved) | Treatment of erectile dysfunction (ED) in adult men |
|---|---|
| Off-label |
|
Dosing According to Clinical Indications
| Population | Indication | Recommended Dose | Notes |
|---|---|---|---|
| Adult males | Erectile Dysfunction | 50 mg once when needed, 1 hour before sexual activity (adjust 25–100 mg as needed) | Max once daily |
| Elderly (≥65 years) | Erectile Dysfunction | 25 mg initially; titrate as tolerated | Increased sensitivity |
| Renal/hepatic impairment | Erectile Dysfunction | 25 mg initially | Consult doctor; close monitoring |
| Children & Adolescents | Not indicated | Do not use | Safety not established |
Safety Profile & Side Effects
Most people tolerate sildenafil well, but like any medicine, it can cause side effects. Seek urgent medical attention for severe allergy, chest pain, or persistent erection (>4 hours).
| Frequency | Side Effect | Advice |
|---|---|---|
| Common (>1/10) | Headache, flushing, nasal congestion, dyspepsia, dizziness | Mild, usually short-lived; rest and hydrate |
| Uncommon (1/100–1/10) | Visual disturbance (blue/blurred vision), indigestion, back pain | Usually not serious; speak to doctor if persistent |
| Rare (<1/1,000) | Priapism (prolonged erection), sudden hearing or vision loss, allergy | Seek urgent medical attention |
| Warnings | Risk higher with nitrate use or significant heart/circulation disease | Careful screening/consultation essential |
Guidelines for Proper Use
- Always follow your doctor’s or pharmacist’s instructions.
- Take the tablet whole with water; never split or crush unless advised.
- Do not exceed the recommended dose or take more than one tablet per day.
- Do not use with nitrate-containing medicines or recreational ‘poppers’.
- Limit or avoid alcohol to reduce side effects.
- Store below 25°C, away from moisture and children.
- Describe all medications—prescribed, herbal, or recreational—to your healthcare provider.
- If you experience chest pain, dizziness, or any sudden serious symptom after taking, seek urgent care.
Alternative Treatment Options
- Tadalafil (Cialis, generic): Longer duration (up to 36 hours), flexible dosing. May allow for more spontaneity, but greater drug exposure.
- Vardenafil (Levitra, generic): Similar mechanism/duration; alternative for those not responding to sildenafil.
- Avanafil (Stendra): Newer agent, faster onset, but less available and not PBS listed.
- Non-drug options: Vacuum erection devices, penile implants, psychological therapies.
Pros & Cons:
- Sildenafil is usually the most affordable and widely studied, but may be less convenient for prolonged intimacy compared to tadalafil.
- Tadalafil can be used once daily for men with frequent sexual activity.
- Consult your prescriber for the most appropriate choice based on your lifestyle and health status.
Legal, Registration, and Reimbursement Status in Australia
- Medicines containing sildenafil for ED (such as Viagra, Sildegra) are registered with the Therapeutic Goods Administration (TGA).
- Prescription required (Schedule 4): Illegal to supply without a written prescription from a registered medical practitioner.
- Vega Extra Cobra is not TGA-registered and is not available via community pharmacy or PBS. Importing unregistered brands for personal use may carry legal and safety risks.
- Not subsidised on the Pharmaceutical Benefits Scheme (PBS) for ED. All costs are borne by the patient.
- Special brands/strengths for pulmonary hypertension may be PBS-reimbursed under specialist plan.
Latest Research and Clinical Guidance (2022–2025)
- 2022: Australian and international guidelines confirm sildenafil remains the first-line drug for erectile dysfunction due to its strong efficacy and safety evidence (see: Andrology Australia).
- 2023: Evidence supports benefit in men with ED after prostate cancer treatment and in those with cardiovascular disease under stable management (Smith et al, Med J Aust 2023).
- 2024: Meta-analyses confirm rare, but possible visual and auditory side effects; prompt cessation and review recommended if these occur.
- 2025: Ongoing research into once-daily dosing and combined therapies for patients with complex comorbidity (Australian Urological Society updates).
Availability and Delivery in Australia
| Pack Size* | Indicative Price (AUD) | Delivery Times (Business Days) |
|---|---|---|
| 4 tablets (100 mg) | $25–35 | Sydney: 0–1, Melbourne: 1–2, Brisbane: 1–3, Perth: 3–5, Adelaide: 1–3 |
| 8 tablets (100 mg) | $50–60 | As above |
| 28 tablets (100 mg) | $155–165 | As above |
*Unregistered/online imports (such as Vega Extra Cobra) are not guaranteed as safe or legal and are not recommended for use in Australia. Only buy from registered Australian pharmacies.
Frequently Asked Questions (FAQ)
- Can I buy Vega Extra Cobra or sildenafil without a prescription in Australia?
No. All sildenafil medicines for ED (including Viagra and generic equivalents) require a valid prescription in Australia. Buying unregistered brands online is not recommended due to quality and legal risks. - How long does sildenafil take to start working, and how long does it last?
It usually starts to work within 30–60 minutes. Peak effect is about one hour after taking, and it lasts for up to 4–6 hours. Sexual stimulation is necessary for effect. - Can I drink alcohol with Vega Extra Cobra or sildenafil?
Try to limit or avoid alcohol as it can increase the risk of side effects (such as dizziness or fainting) and may reduce efficacy. Excessive alcohol can also contribute to ED itself. - Can women or children use sildenafil for sexual dysfunction?
No. Sildenafil is only approved for use in adult men with ED. Its safety for women (except in some types of pulmonary hypertension) and children is not established. - What should I do if I experience side effects or no effect?
If you get mild side effects, rest and inform your doctor during your next visit. For severe side effects, like chest pain, vision changes, or a prolonged erection (>4 hours), seek immediate medical care. If you don’t achieve the desired effect, speak to your GP; do not increase the dose on your own.
Always consult your doctor or a registered Australian pharmacist before starting or changing any medicine for erectile dysfunction. You can find more patient information at NPS MedicineWise or speak directly to your local pharmacy.
