Sildenafil: Dosage, Side Effects, and ED Treatment Explained

Summary or Key Points

Sildenafil is a prescription medication commonly used to treat erectile dysfunction (ED), pulmonary arterial hypertension (PAH), and other conditions. It works by relaxing blood vessels, which improves blood flow to specific areas of the body. Sildenafil is available in various forms and strengths. Always consult a healthcare provider before starting or adjusting your dose. Our telemedicine providers are available to assist with any questions or concerns you may have.

Names of Medication

US Brand Name: Viagra (Sildenafil)

US Brand Name: Revatio (Sildenafil)

The generic name refers to the chemical composition of the drug, while the brand name is assigned by the manufacturer. In this article, the generic name is listed in parentheses.

Pharmacologic Category

Phosphodiesterase-5 (PDE-5) Inhibitors

Sildenafil Dosage

Sildenafil is prescribed for various conditions, with the dosage depending on the specific condition being treated. Always follow your healthcare provider’s instructions and consult them before making any changes to your dose. Our telemedicine providers can guide you through this process.

Erectile Dysfunction (ED) Treatment

Initial dose: 50 mg taken orally as needed, approximately 1 hour before sexual activity.

Maintenance dose: 25 mg to 100 mg as needed, based on effectiveness and tolerance.

Maximum dose: 100 mg per day.

Sildenafil for Pulmonary Arterial Hypertension (PAH)

Revatio: 5 mg or 20 mg taken orally three times a day, 4-6 hours apart.

Maximum dose: 20 mg three times a day.

Raynaud’s Phenomenon (Off-Label Use)

50 mg taken orally twice daily.

Consult your healthcare provider for the appropriate dose.

Altitude Sickness (Off-Label Use)

50 mg taken orally every 8 hours.

Consult your healthcare provider for the appropriate dose and duration.

Heart Failure (Off-Label Use)

25 mg to 50 mg taken orally three times a day.

Consult your healthcare provider for the appropriate dose.

Benign Prostatic Hyperplasia (BPH) (Off-Label Use)

25 mg to 50 mg taken orally once daily.

Consult your healthcare provider for the appropriate dose.

Chronic Obstructive Pulmonary Disease (COPD) (Off-Label Use)

20 mg taken orally three times a day.

Consult your healthcare provider for the appropriate dose.

Pulmonary Hypertension

Revatio: 5 mg or 20 mg taken orally three times a day, 4-6 hours apart.

Maximum dose: 20 mg three times a day.

Sexual Dysfunction (Related to Antidepressant Use)

Off-label use: 50 mg taken orally 1 hour before sexual activity.

Consult your healthcare provider for the appropriate dose.

Hypertension (Off-Label Use)

20 mg taken orally three times a day.

Consult your healthcare provider for the appropriate dose.

Dosage Forms and Strengths

Tablets: 25 mg, 50 mg, 100 mg

Oral suspension: 10 mg/mL

Injection: 10 mg/12.5 mL (1.12 mg/mL)

Administration Instructions for Sildenafil

Sildenafil should be taken exactly as directed by your healthcare provider. For erectile dysfunction, take it about 30 minutes to 1 hour before sexual activity. It can be taken with or without food, but high-fat meals may delay its effect. For pulmonary arterial hypertension, take it at evenly spaced intervals throughout the day. Do not exceed the recommended dose. If you miss a dose, take it as soon as you remember, but do not double up on doses.

Sildenafil Side Effects and Adverse Reactions

Like all medications, Sildenafil can cause side effects. Some are common and mild, while others are less common but more serious. If you experience any side effects, contact your healthcare provider immediately. Our telemedicine providers are available to help you manage any side effects or concerns.

Common Sildenafil Side Effects

Headache: Mild to moderate headaches are a common side effect.

Flushing: A sensation of warmth or redness in the face, neck, or chest.

Indigestion: Stomach discomfort or heartburn may occur.

Nasal Congestion: A stuffy or runny nose is a frequent side effect.

Less Common but Serious Side Effects

Vision Changes: Blurred vision or changes in color perception. Seek medical attention if this occurs.

Hearing Loss: Sudden decrease or loss of hearing. Contact your healthcare provider immediately.

Priapism: An erection lasting more than 4 hours. This is a medical emergency and requires immediate attention.

Chest Pain: If you experience chest pain, stop taking Sildenafil and seek medical help right away.

Contraindications for Sildenafil Use

A contraindication is a specific situation or condition where a particular medication should not be used because it may cause harm. If you have any of the following conditions, taking Sildenafil may not be safe for you. Always consult with one of our telemedicine providers before starting or stopping any medication.

Severe heart or liver problems: Sildenafil can affect blood flow and may put additional strain on your heart or liver. If you have severe heart conditions (such as a recent heart attack or stroke) or liver disease, this medication could worsen your condition.

Low blood pressure (hypotension): Sildenafil can lower your blood pressure further, which could lead to dizziness, fainting, or even a dangerous drop in blood pressure.

Recent stroke or heart attack: If you’ve had a stroke or heart attack within the last 6 months, Sildenafil may increase your risk of another cardiovascular event due to its effects on blood flow and blood pressure.

Use of nitrates: Nitrates (often used for chest pain) and Sildenafil both lower blood pressure. Taking them together can cause a significant and dangerous drop in blood pressure.

Severe vision loss: If you have a condition called non-arteritic anterior ischemic optic neuropathy (NAION), taking Sildenafil could increase the risk of further vision loss.

Allergy to Sildenafil: If you have had an allergic reaction to Sildenafil or any of its ingredients, you should not take this medication.

Drug to Drug Interactions

Certain medications can interact with Sildenafil, either reducing its effectiveness or increasing the risk of side effects. It’s important to inform your healthcare provider about all the medications you are currently taking, including over-the-counter drugs and supplements. Below are some common medications that may interact with Sildenafil:

1. Nitrates (e.g., nitroglycerin, isosorbide dinitrate): These are used to treat chest pain (angina). When combined with Sildenafil, they can cause a dangerous drop in blood pressure.
2. Alpha-blockers (e.g., doxazosin, tamsulosin): These medications are used to treat high blood pressure or prostate conditions. Taking them with Sildenafil can result in a significant drop in blood pressure.
3. Protease inhibitors (e.g., ritonavir, indinavir): Commonly used to treat HIV, these drugs can increase the levels of Sildenafil in your blood, raising the risk of side effects.
4. Antifungal medications (e.g., ketoconazole, itraconazole): These can also elevate Sildenafil levels in the bloodstream, increasing the likelihood of side effects.
5. Blood pressure medications (e.g., amlodipine, lisinopril): Sildenafil can enhance the blood pressure-lowering effects of these drugs, potentially leading to hypotension (low blood pressure).

Sildenafil in Pregnancy

Is it Safe to Take Sildenafil When Pregnant?

Sildenafil is generally not recommended during pregnancy unless specifically prescribed for conditions like pulmonary arterial hypertension (PAH). Research on its safety in pregnant women is limited, so it should only be used if the potential benefits outweigh the risks. If you are pregnant or planning to become pregnant, consult one of our telemedicine providers to discuss your options.

Sildenafil While Breastfeeding

Is it Safe to Take Sildenafil While Breastfeeding?

There is limited information on whether Sildenafil passes into breast milk. Due to the potential risk to a nursing infant, it is generally advised to avoid Sildenafil while breastfeeding unless prescribed for a specific condition. Always consult your healthcare provider before taking any medication while breastfeeding.

Estimated Cost of Medication

The cost of a 30-day supply of Sildenafil can vary depending on your location and pharmacy. Without insurance, the estimated cost using a GoodRX coupon is approximately $10 to $20 for generic Sildenafil. Branded versions, such as Viagra, are significantly more expensive, ranging from $400 to $500 for a 30-day supply. Be sure to check with your pharmacy for the most accurate pricing.

Possible Alternatives to Sildenafil

If Sildenafil is not suitable for you, other treatment options are available depending on your condition. Always discuss alternatives with your healthcare provider before making any changes to your treatment plan. You can also schedule a telemedicine appointment with one of our providers to explore your options.

1. Erectile dysfunction treatment: Alternatives include other PDE5 inhibitors like Tadalafil (Cialis) or Vardenafil (Levitra). Lifestyle changes, such as regular exercise, weight loss, and quitting smoking, may also improve erectile function.
2. Pulmonary arterial hypertension: Medications like Bosentan (Tracleer) or Epoprostenol (Flolan) may be prescribed. Oxygen therapy and lifestyle changes, such as reducing salt intake, can also help manage symptoms.
3. Raynaud’s phenomenon: Calcium channel blockers like Nifedipine or lifestyle changes, such as avoiding cold exposure and managing stress, may help reduce symptoms.
4. Altitude sickness:Acetazolamide (Diamox) is often used to prevent altitude sickness. Gradual ascent and staying hydrated are also important preventive measures.
5. Heart failure: Medications like beta-blockers, ACE inhibitors, or diuretics may be used. Lifestyle changes, such as reducing salt intake, exercising regularly, and managing stress, are also important.
6. Benign prostatic hyperplasia (BPH): Alpha-blockers like Tamsulosin (Flomax) or 5-alpha-reductase inhibitors like Finasteride (Proscar) are common alternatives. Lifestyle changes, such as reducing caffeine and alcohol intake, may help relieve symptoms.
7. Chronic obstructive pulmonary disease (COPD): Inhalers, bronchodilators, and corticosteroids are common treatments. Quitting smoking and pulmonary rehabilitation may also improve lung function.
8. Pulmonary hypertension: Other medications like Ambrisentan (Letairis) or Epoprostenol (Flolan) may be prescribed. Lifestyle changes, such as reducing salt intake and avoiding strenuous activity, can also help manage symptoms.
9. Sexual dysfunction: Counseling, hormone therapy, or other medications may be alternatives. Lifestyle changes, such as reducing stress and improving communication with your partner, can also be beneficial.
10. Hypertension: Other blood pressure medications, such as ACE inhibitors, beta-blockers, or diuretics, may be used. Lifestyle changes, such as reducing salt intake, exercising regularly, and managing stress, are also important.

Recent Updates on Sildenafil Research

Recent studies have explored the potential use of Sildenafil beyond its current indications. For example, ongoing research is investigating its effectiveness in treating conditions such as heart failure and Raynaud’s phenomenon. Early studies show promise in using Sildenafil to improve blood flow in these conditions, but more research is needed to confirm its safety and effectiveness. Additionally, research continues into Sildenafil’s potential for improving outcomes in patients with pulmonary hypertension and other cardiovascular diseases.

As always, consult your healthcare provider before considering any new or experimental treatments. If you have questions about Sildenafil or its potential uses, schedule a telemedicine appointment with one of our providers today.

James Kingsley

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