Sildenafil

Sildenafil blocks the enzyme PDE5 in the corpus cavernosum, which allows cGMP levels to rise when you are sexually aroused. This improves the smooth muscle relaxation and blood flow needed for an erection. Sildenafil does not cause an erection on its own — sexual stimulation is still required.

Onset is typically 30–60 minutes. Most men take a dose about one hour before intended intimacy. Effect may be delayed or reduced if taken immediately after a heavy or fatty meal.

The active window is around 4 hours. Outside that window you should not expect a response — but you also should not take a second dose within 24 hours.

Both are PDE5 inhibitors. Sildenafil is short-acting (~4-hour window) and taken on-demand. Tadalafil daily (2.5mg or 5mg) is taken every day and works continuously. Your pharmacist decides which is more appropriate based on frequency of intimacy, side-effect history, and other medicines you take.

Moderate alcohol is acceptable. Heavy drinking lowers blood pressure further (on top of sildenafil), worsens side effects, and impairs erectile response in its own right. Keep intake modest.

Don't double the dose yourself. Message the pharmacist team — they may titrate up to 100 mg if clinically appropriate, or switch you to a different agent. Effectiveness is also influenced by timing, food, alcohol, anxiety, and underlying cardiovascular or psychogenic factors, so reviewing these matters.

The Goldstein (1998) pivotal trial included men with organic, psychogenic, and mixed ED. PDE5 inhibitors can support the erectile response regardless of cause, but mental health and relationship factors usually also need attention — your pharmacist may recommend alongside psychological or relationship support.

Headache (roughly 1 in 6 users), facial flushing, nasal congestion, indigestion, and transient visual changes (blue tint, light sensitivity) are the most frequently reported effects. Most are short-lived and dose-related.

No — absolutely not. Combining sildenafil with any nitrate medicine (e.g. GTN spray, isosorbide mononitrate, amyl nitrite/'poppers') can cause severe, potentially fatal drops in blood pressure. This is a strict contraindication. If you are ever prescribed nitrates for chest pain, stop sildenafil.

ED and cardiovascular disease share risk factors, so your pharmacist will check blood pressure, cardiovascular history, and current medications before supplying or prescribing sildenafil. It is generally avoided in recent MI or stroke (last 6 months), severe cardiac failure, unstable angina, or severe hypotension. Disclose your full history at consultation.

Rarely, yes. If you develop an erection lasting more than 4 hours — or a painful erection at any duration — seek urgent medical attention. Untreated priapism can cause permanent erectile tissue damage.

Stop sildenafil immediately and seek urgent medical attention. Sudden vision loss (NAION) and sudden hearing loss have been reported rarely with PDE5 inhibitors and require prompt assessment.

Many blood pressure medicines are compatible — but alpha-blockers (e.g. tamsulosin, doxazosin) need special care because both lower blood pressure, and there is a specific risk of symptomatic hypotension. Disclose all medicines at consultation so your pharmacist can check interactions.

No — combining with amyl nitrite ('poppers'), cocaine, or MDMA is unsafe and the combination with nitrates can be fatal. Be honest with your pharmacist at consultation; your information is confidential under UK GDPR.

In discreet, unbranded packaging with a generic sender name, sent by DPD tracked delivery. Nothing on the outside indicates the contents.

Both. Sildenafil is on-demand medicine, so you can order packs (typically 8 tablets) when you need them. Many patients set up repeat orders for convenience.

No — store at room temperature, away from direct sunlight and moisture.

Any time. Pause, skip, or cancel from your Caremacy account with no notice period or fees.

A qualified clinician reviews every request. Sildenafil 25mg and 100mg are POM; 50mg can follow a Pharmacy (P) supply route. Cardiovascular suitability, interactions, and ED history are reviewed before supply, and treatment is declined where inappropriate.

Yes. Consultations and medical data are stored securely under UK GDPR. Only the pharmacists involved in your care access them. Nothing is shared with third parties for marketing.

We recommend telling your GP for continuity — especially if you have any cardiovascular history or take other medicines. We can also send a record to your GP with your explicit consent.

Yes, through secure messaging in your Caremacy dashboard. For anything severe (sudden vision or hearing loss, prolonged erection, chest pain) stop treatment and seek urgent medical attention immediately.