Fildena (Sildenafil Citrate) — Patient Information for Australia

Fildena contains sildenafil citrate, a medicine used to treat certain conditions related to blood flow to the penis (erectile dysfunction) and—when prescribed for appropriate indications—pulmonary arterial hypertension. This page explains how sildenafil works, how it is typically used, and important safety information to help you make informed decisions.

Please note: Medicines can affect people differently. Always read the consumer medicine information (CMI) and follow your healthcare professional’s advice.

Basic product information

How Fildena works (mechanism of action)

Sildenafil belongs to a group of medicines called phosphodiesterase type 5 (PDE5) inhibitors. In simple terms, it works by:

• Increasing levels of cyclic GMP in smooth muscle cells in blood vessels.
• Allowing relaxation of blood vessels and improved blood flow.
• Helping achieve and maintain an erection in response to sexual stimulation (for erectile dysfunction).

Important: Sildenafil does not create sexual desire. It supports the physiological process needed for an erection when you are sexually stimulated.

Pharmacokinetics (how the body handles sildenafil)

“Pharmacokinetics” describes how the medicine is absorbed, distributed, metabolised, and eliminated.

• Absorption: Sildenafil is absorbed through the digestive tract. Peak blood levels usually occur after about 1–2 hours for many people, though this can vary.
• Distribution: It spreads throughout the body and binds to blood proteins.
• Metabolism: Sildenafil is mainly broken down in the liver, primarily by CYP3A4 (and to a lesser extent CYP2C9).
• Elimination: The medicine and its metabolites are removed mostly through faeces and urine.
• Duration: Effects may last several hours. Many people notice results within the first hours after taking sildenafil, with varying “window of opportunity.”

Because metabolism involves liver enzymes, medicines that affect these enzymes (and substances that affect blood flow) may change how sildenafil works for you.

Typical use and timing

For erectile dysfunction (ED)

Fildena is commonly used to treat erectile dysfunction, helping men achieve and maintain an erection during sexual activity.

Timing:

• Many people take sildenafil about 30–60 minutes before sexual activity.
• Some may find it works best closer to 1 hour, while others may need more or less time.
• If you notice food delays the effect, you may need to adjust timing (see food interactions below).

For pulmonary arterial hypertension (PAH)

Sildenafil may be used in pulmonary arterial hypertension under appropriate medical direction and product selection. If you are using sildenafil for PAH, your dosing schedule may differ from ED dosing. Always follow the instructions provided for your specific condition.

Indications (what it is used for)

Sildenafil is indicated for:

• Erectile dysfunction (difficulty getting or maintaining an erection sufficient for satisfactory sexual performance).
• Pulmonary arterial hypertension (in adults, for improvement of exercise capacity and symptoms, when appropriate).

Reassurance: For ED, sildenafil is effective for many people, but results vary. It is most effective when taken correctly and used with sexual stimulation.

Dosing: general guidance

Dosing depends on the condition being treated, your age, other medicines, kidney/liver function, and individual response. Product strengths vary, so always check the label and the instructions supplied with your medicine.

For erectile dysfunction (common approach):

• Start with a lower dose if you are older or more sensitive to side effects.
• Take no more than the recommended frequency on the product information.
• Do not “top up” frequently to extend effects; if a dose doesn’t work, discuss adjustment with a healthcare professional rather than increasing yourself.

Special populations:

• Liver impairment: Some people may require lower dosing due to slower metabolism.
• Kidney impairment: Dose adjustments may be required depending on severity.
• Older adults: Sensitivity to side effects may be higher, and a lower starting dose is often considered.

What to avoid with dosing:

• Do not combine sildenafil with another PDE5 inhibitor (e.g., tadalafil, vardenafil, or similar) at the same time.
• Do not exceed the dosing frequency stated on the product information.

If you’re unsure which strength or schedule is appropriate for you, seek personalised advice.

Food interactions (what to eat and drink)

Food—especially high-fat meals—can affect how quickly sildenafil works.

• High-fat meals: Can delay absorption and postpone when you notice the effect.
• Light meals: Usually have less effect on timing.

Practical tip: If you plan to take sildenafil, consider having a lighter meal beforehand or allow extra time after a heavier meal.

Alcohol interactions

Alcohol can affect erections by reducing blood pressure and increasing relaxation of blood vessels. When combined with sildenafil, this may increase the likelihood of side effects such as dizziness or .

• Moderate alcohol may be tolerated by some people, but excess alcohol can significantly reduce erection quality.
• If you feel dizzy or faint after taking sildenafil, avoid further alcohol and seek medical advice if symptoms persist.

Safety reminder: Avoid situations where you could fall or be injured if you feel unwell.

Medicine interactions (important safety considerations)

Certain medicines can strongly interact with sildenafil by changing its breakdown, increasing drug levels, or causing dangerous blood pressure changes.

Absolute/major interaction: nitrates and “nitro” medicines

Sildenafil should not be used with nitrates or medicines that release nitric oxide, due to the risk of dangerously low blood pressure. This includes:

• Nitroglycerin (glyceryl trinitrate)
• Isosorbide dinitrate/mononitrate
• Some “poppers” (alkyl nitrites)
• Any nitrate-containing chest pain medicine

Other major interaction: riociguat

• Riociguat (used for pulmonary hypertension) can significantly increase risk of hypotension when combined with sildenafil.

Blood pressure medicines and alpha-blockers

If you take medicines for high blood pressure or prostate symptoms, blood pressure may drop more when combined with sildenafil.

• Alpha-blockers (for example, tamsulosin, doxazosin) may increase risk of low blood pressure and dizziness.

Your clinician may adjust timing or choose a starting dose strategy to reduce risk.

Medicines that increase sildenafil levels (CYP3A4 inhibitors)

Some medicines reduce sildenafil breakdown and can increase side effects. Examples include:

• Some HIV medicines (protease inhibitors)
• Some antifungals (e.g., ketoconazole, itraconazole)
• Macrolide antibiotics (e.g., clarithromycin)
• Other strong CYP3A4 inhibitors

Medicines that may reduce sildenafil levels (CYP3A4 inducers)

These may make sildenafil less effective. Examples include:

• Some seizure medicines
• Some rifamycin antibiotics
• St John’s wort (herbal supplement)

Other sildenafil interactions

• Avoid combining with other PDE5 inhibitors.
• Use caution with medicines that affect cardiovascular status, as sildenafil influences blood flow and blood pressure.

Tell your pharmacist or healthcare professional about all medicines and supplements you take, including non-prescription and herbal products.

Safety profile: common side effects and when to seek help

Like all medicines, sildenafil can cause side effects. Many are mild and temporary, but some require prompt medical attention.

Common side effects

• Headache
• Flushing or warmth in the face
• Indigestion or stomach discomfort
• Blocked or runny nose
• Dizziness
• Visual changes (e.g., altered colour perception or blurred vision) in some people

Serious side effects — seek urgent help

Get medical help immediately if you experience:

• Chest pain or symptoms of a heart problem
• Fainting or severe dizziness
• Sudden vision loss or sudden changes in vision
• Sudden hearing loss
• Prolonged erection (erection lasting longer than recommended/if painful)—this needs urgent treatment
• Severe allergic reaction (swelling of face/lips, difficulty breathing, widespread rash)

Cardiovascular note: Sexual activity can stress the heart. If you have heart disease or symptoms with exertion, discuss ED treatment options with a clinician before use.

Practical use tips for best results

• Take it at the right time: Many people benefit from taking sildenafil 30–60 minutes before activity.
• Consider a lighter meal: A heavy, fatty meal may delay onset.
• Stay within the recommended dose: More is not always better and can increase side effects.
• Allow enough opportunity: Use during a window when you can be sexually stimulated (sildenafil supports response, it doesn’t create desire).
• Don’t “stack” multiple doses quickly: If it doesn’t work, avoid repeated dosing too soon; reassess with healthcare advice.
• Review interactions: Especially with nitrates, riociguat, and blood pressure medicines.
• Be prepared for variability: Stress, sleep, alcohol, smoking, and overall health can influence performance.

Alternative options

Depending on your needs and medical history, there may be other treatment approaches for erectile dysfunction or pulmonary arterial hypertension.

Other PDE5 inhibitors

• Tadalafil (often longer duration for some people)
• Vardenafil
• Avanafil

Non-PDE5 options (discuss with a clinician)

• Vacuum erection devices
• Penile injections or urethral therapy (for suitable patients)
• Psychosexual counselling and lifestyle interventions
• Addressing contributing conditions (e.g., diabetes, cardiovascular health, depression, medication side effects)

If sildenafil isn’t suitable due to interactions or side effects, a healthcare professional can help determine safer alternatives.

Market and legal context for Australia

In Australia, medicines containing sildenafil are regulated under the national medicines framework, and availability may depend on the product type, strength, and how it is supplied through licensed channels.

Key points for Australians:

• Australia follows strict requirements for manufacturing, supply chain integrity, and quality control.
• Online pharmacies should be properly authorised and should provide transparent information about product sourcing and counselling.
• Consumers should be cautious with unregulated products or unclear labelling.

For the most up-to-date regulatory guidance, you can also refer to Australian government and health resources.

Recent guidance and important updates (general)

Guidance can evolve over time, particularly around safe supply, telehealth processes, and medicine quality standards. Recent trends across many countries, including Australia, include:

• Increased emphasis on safe screening for cardiovascular risk and medicine interactions (especially nitrates and certain heart medications).
• Greater attention to authenticity and supply chain to reduce the risk of counterfeit or substandard products.
• Clearer patient-facing education about side effects that need urgent assessment (vision changes, prolonged erection, chest pain).

Always use current local information provided by Australian health services and reputable pharmacists.

Delivery and availability

Availability and delivery options depend on the pharmacy you choose, stock levels, and the shipping destination within Australia.

When ordering online, look for:

• Clear product listing (strength, tablet count, and active ingredient)
• Secure payment and identifiable pharmacy/medical governance
• Shipping times and tracking details
• Packaging quality and product authenticity assurances
• Customer support for dosing questions and interaction concerns

Storage: Keep tablets in a cool, dry place and follow the storage instructions on the label. Keep medicines out of reach of children.

FAQ — Fildena (Sildenafil Citrate)

1) How soon does Fildena work?

Many people notice effects within 30–60 minutes. Peak effect is often around 1–2 hours. A heavy, fatty meal may delay onset.

2) How long do the effects last?

Effects may last for several hours, but the exact duration varies by person, dose, and whether food or alcohol is involved.

3) Can I take Fildena with food?

Yes, but if you eat a high-fat meal, you may experience a delayed onset. A lighter meal may work better for timing.

4) Is it safe to drink alcohol while using sildenafil?

Small amounts may be tolerated, but alcohol can worsen erections and increase the chance of dizziness. Avoid heavy drinking.

5) What should I do if I get side effects?

Mild side effects (such as headache or flushing) usually settle. If you experience severe symptoms—especially chest pain, fainting, sudden vision/hearing changes, or a prolonged erection—seek urgent medical care.

6) Can I take sildenafil if I have heart problems?

Sexual activity and sildenafil may not be appropriate for everyone. Because sildenafil affects blood flow and blood pressure, it’s important to discuss your cardiovascular history with a clinician before use.

7) Why doesn’t it work for me?

Possible reasons include incorrect timing, a heavy meal, insufficient sexual stimulation, stress, alcohol use, or interacting medicines. Underlying conditions (such as diabetes or vascular disease) can also affect response.

8) Can I combine Fildena with other ED medicines?

Do not combine sildenafil with another PDE5 inhibitor. Combining with nitrates is also dangerous. If you’re unsure, ask a pharmacist.

9) What medicines must I avoid?

Do not use sildenafil with nitrates (including certain chest pain medicines) or with riociguat. Also use caution with alpha-blockers and medicines that affect CYP3A4 metabolism.

10) Is Fildena only for erectile dysfunction?

Sildenafil is used for erectile dysfunction and can also be used for pulmonary arterial hypertension in appropriate patients under the relevant regimen.

Disclaimer: This information is general and designed for patient education. It does not replace advice from a healthcare professional. If you have questions about suitability, interactions, or dosing, contact a pharmacist or clinician.