Stendra (Avanafil) – Patient Information (UK)

Stendra is a brand of avanafil, a medicine used to treat erectile dysfunction (ED) in adult men. This page explains how Stendra works, how to take it safely and effectively, key interactions (including alcohol and food), and what to expect. It is written for patients in the United Kingdom and aims to be clear and practical.

What is Stendra?

Stendra (avanafil) is an oral ED treatment that belongs to the class of medicines called PDE5 inhibitors. These medicines help you achieve and maintain an erection suitable for sex by improving blood flow in the erectile tissue.

Stendra is designed to be taken before sexual activity. It does not automatically cause an erection—sexual stimulation is still required.

How Stendra works (mechanism of action)

Erection depends on blood flow to the penis. During sexual arousal, the body releases nitric oxide, which increases levels of cGMP (cyclic guanosine monophosphate). cGMP helps relax smooth muscle in the penile blood vessels, allowing increased blood flow.

Avanafil works by blocking PDE5 (phosphodiesterase type 5), an enzyme that breaks down cGMP. By inhibiting PDE5, Stendra helps cGMP last longer, supporting blood vessel relaxation and improved erectile response to sexual stimulation.

Key point: Stendra enhances the normal erectile pathway in response to sexual stimulation. It is not a hormonal treatment and does not increase libido by itself.

Pharmacokinetics (how the body handles avanafil)

Pharmacokinetics describes what happens after you take a medicine—how it is absorbed, distributed, metabolised, and eliminated.

• Absorption: Avanafil is absorbed after oral administration. Peak levels generally occur within about 30–90 minutes, but this can vary.
• Onset: Many people notice effects within 15–30 minutes. Optimal timing depends on individual factors and the presence of food.
• Metabolism: Avanafil is mainly processed in the body by the liver enzyme system, particularly CYP3A4.
• Elimination: Metabolites are cleared primarily via the liver and biliary routes. A smaller portion is eliminated through the kidneys.
• Variability: Age, liver function, kidney function, and interacting medicines can affect exposure and response.

What Stendra is used for (indications)

Stendra is indicated for the treatment of erectile dysfunction (ED) in adult men. ED is the consistent difficulty achieving or maintaining an erection sufficient for satisfactory sexual performance.

Stendra should only be used for ED when appropriate. If you have chest pain, unstable heart disease, or other serious cardiovascular conditions, it’s important to discuss safety with a healthcare professional before using any PDE5 inhibitor.

Typical dosing and how to take Stendra

Always follow the dosing instructions provided by your healthcare professional or pharmacy advice. The information below gives general guidance commonly used with avanafil.

Starting dose (general approach)

• Common starting dose: 100 mg, taken as needed before sexual activity.
• Adjustment: Depending on tolerability and response, the dose may be adjusted to 50 mg (lower) or 200 mg (higher).
• For some patients: A lower starting dose may be advised when risk factors or interacting medicines are present (for example, certain liver problems or certain drug interactions).

Timing before sex

• Take Stendra approximately 15–30 minutes before sexual activity.
• In some cases, taking earlier or later may change effectiveness. If you don’t respond, do not simply increase frequency—discuss options with a clinician.

How often to take it

• Stendra is typically taken as needed, not on a fixed daily schedule.
• Do not take more than once per day.

Swallowing and preparation

• Swallow the tablet whole with water.
• Try to take it consistently relative to meals for best predictability.

When Stendra works best (timing and meal effects)

Food can influence how quickly avanafil reaches peak levels. This can affect how fast it works and how reliable it feels from dose to dose.

Food interactions

• High-fat meals: These may delay absorption and reduce or delay the effect. If possible, avoid taking Stendra immediately after a heavy or high-fat meal.
• Fasting or light meals: Many people find the medicine works more predictably when taken on a lighter stomach or after a shorter gap from eating.

Practical tip: If you plan an evening meal, consider taking Stendra after the meal rather than immediately with it, and avoid very heavy, greasy foods.

Alcohol and Stendra

Alcohol can affect erections in two ways: it can reduce the body’s ability to achieve erection (through effects on blood vessels and nerves), and it can worsen side effects such as dizziness or low blood pressure.

• Moderate alcohol: Some men may still get good results, but effectiveness can vary.
• Heavy alcohol: More likely to reduce erection quality and increase side effects like light-headedness.
• Safety consideration: Avoid excessive drinking, especially if you are prone to low blood pressure or are taking medicines that affect blood pressure.

If you feel dizzy, unwell, or your erection doesn’t respond as expected, allow time for alcohol to clear and consider discussing dose timing and tolerability with a healthcare professional.

Medicine interactions (important)

Some medicines can strongly interact with avanafil, changing its levels in the body or increasing the risk of dangerous side effects (particularly low blood pressure).

Do NOT combine with nitrates

Very important: PDE5 inhibitors like avanafil must not be used with nitrates (for example, glyceryl trinitrate/nitroglycerin, isosorbide dinitrate, isosorbide mononitrate) because the combination can cause a dangerous drop in blood pressure.

If you use nitrates for angina, do not take Stendra and seek medical advice urgently for safer ED options.

Alpha-blockers (prostate/BP medicines)

Some men take alpha-blockers such as tamsulosin or doxazosin. Combining these with PDE5 inhibitors may lower blood pressure in certain people.

• Using PDE5 inhibitors may be possible with careful timing and stable dosing, but a clinician must advise on the safest approach.
• Start low and monitor symptoms such as dizziness or faintness.

Other PDE5 inhibitors

Do not combine Stendra with other ED PDE5 inhibitors (such as sildenafil, tadalafil, or vardenafil). Doubling up increases side effects without improving safety.

Potent CYP3A4 inhibitors (may raise avanafil levels)

Avanafil is metabolised by CYP3A4. Medicines that strongly inhibit CYP3A4 can raise avanafil levels, increasing side effects.

• Examples include some antifungals (e.g., ketoconazole, itraconazole), macrolide antibiotics (e.g., clarithromycin), and certain antivirals used for HIV or hepatitis.
• If you take such medicines, a dose reduction or avoidance of use may be required.

CYP3A4 inducers (may reduce effectiveness)

Medicines that strongly activate CYP3A4 can lower avanafil levels, potentially reducing effect.

• Some anticonvulsants and certain antibiotics can act as inducers.
• You may need a clinician review to adjust strategy.

Blood pressure medicines

Because ED and blood pressure are both linked to vascular function, combining avanafil with multiple blood pressure-lowering medicines can increase the risk of light-headedness or falls.

Take extra care if you already experience dizziness on standing (orthostatic hypotension).

Safety profile and side effects

Most people tolerate Stendra well, but like all medicines it can cause side effects. The following list includes commonly reported effects and key warning symptoms.

Common side effects

• Headache
• Flushing (warmth/redness)
• Stuffy or runny nose
• Dizziness
• Indigestion or nausea

Less common but important symptoms

• Vision changes (e.g., sudden blurred vision)
• Hearing changes (e.g., sudden decreased hearing or ringing)
• Chest pain or severe dizziness

Emergency warning signs – seek urgent help

Stop using Stendra and seek urgent medical attention if you experience:

• Prolonged erection (priapism) lasting 4 hours or more
• Chest pain, fainting, or severe shortness of breath
• Sudden vision loss or sudden hearing loss
• Signs of severe allergic reaction (swelling of the face/lips, difficulty breathing)

Who should use extra caution?

• Men with known heart disease or significant cardiovascular symptoms
• Men taking medicines that interact with avanafil (especially nitrates or strong CYP3A4 inhibitors)
• Men with certain liver problems (dose adjustments or avoidance may be needed)
• Those with a history of priapism or certain blood cell disorders

Practical use tips for better results

• Plan ahead: Take it at the right time before sex. Many people aim for 15–30 minutes, but adjust for your personal response.
• Choose timing relative to meals: Avoid heavy, fatty meals right around dosing to reduce delays.
• Don’t exceed the frequency: More often does not mean better and increases side effects.
• Use with sexual stimulation: Stendra helps your body respond to arousal; it is not a stand-alone trigger.
• Stay aware of dizziness: If you feel light-headed, sit down and avoid driving until you feel normal.
• Consider ED causes: If ED is new, worsening, or associated with other symptoms (pain, libido changes, urinary symptoms), get medical advice—ED can be linked to blood vessel health and hormonal or neurological factors.

Typical expectations

ED treatments often require a few attempts to find the timing that works best. If you don’t notice any effect:

• Check your meal timing and alcohol intake.
• Confirm you are using it once daily at most.
• Consider whether your other medicines might reduce effectiveness.
• Discuss whether a dose adjustment is appropriate.

Alternative options for ED

There are several alternatives to Stendra. The best choice depends on your health profile, other medicines, and how quickly you want effects.

Other PDE5 inhibitors

• Sildenafil (often taken 30–60 minutes before sex)
• Tadalafil (longer duration; can be taken as needed or in some cases daily per clinician advice)
• Vardenafil (timing varies)

Non-PDE5 options

• Vacuum erection devices (mechanical approach)
• Injections or intraurethral therapy (clinician-directed)
• Psychosexual support if anxiety/performance stress is a factor
• Lifestyle measures: stopping smoking, reducing excess alcohol, exercise, and managing weight can improve ED over time

If you cannot take PDE5 inhibitors due to interactions (for example, nitrate use), discuss safer alternatives with a healthcare professional.

UK market and legal context (how it is typically handled)

In the United Kingdom, medicines containing avanafil are regulated and must be supplied in line with UK pharmaceutical rules. Availability may vary by strength and manufacturer supply. Online pharmacies in the UK typically operate within established regulatory frameworks, with medicines supplied through approved channels and identity/eligibility checks where required.

Always ensure your supply is from a reputable UK-licensed pharmacy and that packaging and labelling match what is expected for the product.

Recent guidance and clinical considerations

Advice for ED treatment in the UK aligns with broader clinical safety recommendations for PDE5 inhibitors. Key themes include:

• Cardiovascular assessment: ED can share risk factors with heart disease. In men with cardiovascular symptoms, clinicians may assess stability before PDE5 inhibitor use.
• Avoiding dangerous combinations: Nitrates and certain interacting medicines remain a major safety issue.
• Start low and adjust: Dose selection often aims to balance effectiveness with side effects, particularly in older adults or those with comorbidities.
• Monitoring for rare but serious events: Priapism, vision and hearing changes are uncommon but require immediate attention.

If you have concerns about your heart, blood pressure, or current medicines, ask a healthcare professional to review safety before you use Stendra.

Delivery and availability (UK)

Availability of Stendra can depend on supplier stock and the requested strength (commonly 50 mg, 100 mg, 200 mg). Online pharmacy delivery times vary, but most UK services aim to dispatch orders promptly and provide tracking.

• Check stock availability for your preferred strength.
• Verify packaging on arrival and store tablets in a cool, dry place.
• Do not use expired medicines.

If you need specific dosing advice due to other medical conditions or medications, choose a service that offers appropriate patient support and clear guidance.

FAQ – Stendra (Avanafil)

How quickly does Stendra work?

Many people notice effects within about 15–30 minutes. Peak effect can occur later (often within 30–90 minutes), and food (especially heavy, high-fat meals) may delay onset.

What if Stendra doesn’t work for me?

It may be due to dose level, meal timing, alcohol, stress/anxiety, or interacting medicines. Don’t increase frequency. Discuss options with a clinician—sometimes a different strength, timing, or alternative treatment may be needed.

Can I take Stendra every day?

Stendra is typically used as needed. In general, you should not take it more than once per day. If you feel you need daily treatment, talk to a healthcare professional about the safest regimen.

Can I drink alcohol with Stendra?

Moderate alcohol may be tolerated by some men, but alcohol can reduce the quality of erections and increase dizziness or low blood pressure risk. Avoid heavy drinking and be careful about how you feel when you take it.

Can I take Stendra with my blood pressure tablets?

Some blood pressure medicines may increase the risk of dizziness or low blood pressure when combined with PDE5 inhibitors. It may still be possible, but the safest approach depends on your exact medicines and doses—seek advice.

Is Stendra safe to take with nitrates?

No. PDE5 inhibitors like avanafil must not be taken with nitrate medicines due to the risk of dangerous blood pressure drops.

Does Stendra affect libido?

Stendra helps with erections in response to sexual stimulation; it is not a libido (sex drive) medicine. If libido is low, other causes may need assessment.

Can Stendra be taken after a high-fat meal?

High-fat meals can delay absorption and reduce how quickly it works. For best results, avoid taking it immediately after a heavy, fatty meal.

What should I do if I get side effects?

Common side effects include headache, flushing, and nasal congestion. If side effects are severe, persistent, or include chest pain, fainting, vision/hearing changes, or prolonged erection, seek urgent medical help.

What should I do in case of priapism?

If an erection lasts 4 hours or more, seek emergency medical care. Priapism is an emergency due to the risk of tissue damage.

Are there alternatives if I can’t take Stendra?

Yes. Options include other PDE5 inhibitors (if safe for you), vacuum erection devices, and other ED therapies. Your choice depends on your health conditions and other medicines.

Important note

This patient-friendly guide is intended to provide general information about Stendra (avanafil). It does not replace individual medical advice. If you are unsure whether avanafil is suitable for you—especially if you have heart disease, low blood pressure, liver issues, or take medicines such as nitrates—seek appropriate guidance before using ED treatments.