What is Sildenafil?

Sildenafil tablets are a medication commonly used to treat erectile dysfunction (ED) and pulmonary arterial hypertension (PAH). It’s most well-known under the brand name Viagra for ED, but as the patent for this expired it is now available generically. Sildenafil is belongs to a class of drugs known as PDE5 inhibitors. In simple terms they work by increasing blood flow to certain parts of the body, primarily in the penis, making it easier for men with ED to achieve and maintain an erection. For PAH, it helps by relaxing blood vessels in the lungs, reducing blood pressure in the arteries.

How Does Sildenafil Work?

Sildenafil works by inhibiting an enzyme called phosphodiesterase type 5 (PDE5). This enzyme normally breaks down a molecule called cyclic GMP (cGMP), which is responsible for relaxing smooth muscle and dilating blood vessels. By blocking PDE5, sildenafil increases the levels of cGMP, which helps to relax blood vessels and improve blood flow.

For ED, this means that when a man is sexually stimulated, more blood can flow into the penis, leading to an erection. It’s important to note that sildenafil doesn’t cause an erection on its own—sexual stimulation is still required.

For PAH, sildenafil helps reduce pressure in the blood vessels of the lungs, making it easier for the heart to pump blood through them.

Medications You Can Take with Sildenafil

We commonly get asked if it is safe to take sildenafil with certain drugs, so we have compiled a short list of the most commonly asked drugs that are safe to take with Sildenafil.

• Statins: If you have been prescribed a statin (Atorvastatin, Simvastatin, Rosuvastatin) for high chloesterol it is perfectly fine to take sildenafil alongside them.
• Some Blood Pressure Medications: Sildenafil may be taken with certain blood pressure medications however you should monitor your blood pressure more closely, particularly if you are taking calcium channel blockers (Amlodipine) or diuretics (Furosemide, Bendroflumethiazide) as Sildenafil can cause your blood pressure to drop.
• Antacids: If you’re experiencing indigestion while taking sildenafil, it’s generally safe to use antacids like Gaviscon or Rennies. But keep in mind that taking antacids too close to your sildenafil dose could reduce its effectiveness.

Medications to Avoid with Sildenafil

Some medication should not be taken together with Sildenafil as they can interact and have adverse effects.

• Nitrates: Medications like nitroglycerin or isosorbide mononitrate (often used for chest pain or angina) should never be taken with sildenafil. The combination can cause a dangerous drop in blood pressure, leading to dizziness, fainting, or even a heart attack.
• Alpha-Blockers: Drugs like doxazosin or tamsulosin, which are used to treat high blood pressure or benign prostatic hyperplasia (BPH), may also cause a significant drop in blood pressure when combined with sildenafil. Your doctor may need to adjust your dose or monitor you closely.
• Other PDE5 Inhibitors: Avoid using sildenafil with other PDE5 inhibitors like tadalafil (Cialis) or vardenafil (Levitra), as this can increase the risk of side effects such as severe hypotension.
• Certain Antifungals and Antibiotics: Medications like ketoconazole, itraconazole, and some antibiotics like clarithromycin can interact with sildenafil, raising its levels in your bloodstream and increasing the risk of side effects.

How Long Does Sildenafil Last?

Sildenafil typically starts working 30-60 minutes after you take it, and the effects can last for 4 to 5 hours. This doesn't mean you'll have an erection for the entire time, but that you'll find it easier to achieve one when sexually stimulated. After around 4-5 hours, the drug will start to wear off, and its effects will gradually decrease.

Side Effects

Like any medication, sildenafil can cause side effects. Common side effects include:

• Headache
• Flushing
• Dizziness
• Indigestion
• Serious side effects, though rare, can include vision or hearing loss, chest pain, or prolonged erections (priapism). If you experience any severe side effects, you should seek medical attention immediately.

Who Shouldn’t Take Sildenafil?

Sildenafil may not be suitable for everyone. Those with certain conditions should avoid it or use it only under medical supervision. You should avoid sildenafil if you have:

• Severe heart or liver problems
• Low blood pressure
• Recently had a stroke or heart attack
• Certain eye conditions such as retinitis pigmentosa

If you have any concerns if sildenafil is safe for you, speak to your doctor or pharmacist before starting sildenafil.

Summary

Sildenafil is an effective and widely-used treatment for erectile dysfunction and pulmonary arterial hypertension. It works by increasing blood flow and relaxing blood vessels. It’s important to understand how sildenafil interacts with other medications—while some are safe to combine, others, like nitrates, should be strictly avoided. Always follow your healthcare provider’s advice to ensure that sildenafil is safe and effective for you.

Frequently Asked Questions (FAQs)

1. Can you buy sildenafil over the counter??
Yes, if you fill out a short consultation in certain pharmacies you can buy certain brands over the counter. We also offer sildenafil tablets to buy after filling out a short consultation form on our erectile dysfuncton treatments page your tablets will be discreetly posted to you.

2. Does sildenafil work??
Yes, Sildenafil has been found to be effective in 74% of men who take it.

3. How long does it take sildenafil to work?
Sildenafil takes around 30-60 minutes to start to work.

4. How long does sildenafil stay in your system??
Sildenafil takes around 2-6 hours to leave your system, the higher the dosage the longer it takes to leave.

5. How many Sildenafil can i take in a day?
Do not take more than one tablet a day especially if you are taking 100mg tablets.

5. Can I take Sildenafil every day?
Yes you can technically take sildenafil every day. However whether you should or depends on your circumstances. We advise to use it as little as possible and at the lowest strength that gives you a response.

Sources

NHS: Sildenafil
BNF: Sildenafil information
MedicinePlus: Sildenafil
Sildenafil in the treatment of erectile dysfunction: an overview of the clinical evidence