Sildenafil drug bank

Need reliable, up-to-date information on Sildenafil? Start here. This article provides a direct pathway to understanding the drug’s properties, uses, and potential side effects, drawing from trusted sources within the Sildenafil drug bank.

We’ll examine specific data points regarding Sildenafil’s mechanism of action, its approved indications, and common adverse reactions. Expect clear explanations of drug interactions and contraindications, avoiding overly technical jargon.

Key areas covered include dosage recommendations, potential drug interactions, and patient safety considerations. We’ll also highlight resources available within the drug bank itself, empowering you to find answers quickly and accurately. Remember to always consult your physician or pharmacist before making any decisions about your medication.

Sildenafil Drug Bank: A Comprehensive Overview

Consult the DrugBank database directly for the most up-to-date information on Sildenafil. This ensures access to the latest research, safety updates, and potential drug interactions.

Understanding Sildenafil’s Mechanism of Action

Sildenafil inhibits phosphodiesterase-5 (PDE5), increasing cGMP levels. This leads to smooth muscle relaxation in the corpus cavernosum, facilitating penile erection. This mechanism is key to its efficacy in treating erectile dysfunction. However, it’s crucial to understand potential side effects, such as headaches, flushing, and visual disturbances.

Dosage and Administration Considerations

The standard starting dose is typically 50 mg, taken orally as needed, approximately one hour before sexual activity. Dosage adjustments are made based on individual response and potential side effects. Always follow your doctor’s instructions regarding dosage and frequency of administration. Avoid exceeding the recommended dosage without consulting a physician.

Drug Interactions and Contraindications

Sildenafil interacts with nitrates, potentially causing dangerously low blood pressure. It’s contraindicated in patients with severe cardiovascular disease, certain eye conditions, or those taking specific medications. Thorough medical history review is required before Sildenafil prescription. Always inform your doctor about all medications and supplements you are taking.

Monitoring and Side Effect Management

Regular monitoring by a healthcare professional is necessary to assess treatment effectiveness and manage potential side effects. Promptly report any unusual symptoms. These can include severe chest pain, prolonged erection, or sudden vision changes. Your doctor will advise on the best approach for managing any adverse reactions.

Chemical Structure and Properties of Sildenafil

Sildenafil citrate, the active ingredient in Viagra, possesses a unique chemical structure contributing to its pharmacological action. Its core structure includes a pyrazolo[4,3-d]pyrimidine scaffold, substituted with various functional groups. Specifically, a piperazine ring connects to the pyrazolopyrimidine core, along with a sulfonyl group and a substituted phenyl ring. This precise arrangement facilitates binding to specific enzymes.

Structural Features and Activity

The piperazine moiety interacts with the enzyme’s active site. The sulfonyl group enhances lipophilicity, influencing membrane permeability and distribution. The substituted phenyl ring contributes to the molecule’s overall shape and binding affinity. Minor structural modifications can significantly alter Sildenafil’s potency and selectivity.

Physicochemical Properties

Sildenafil is a white or off-white crystalline powder, slightly soluble in water but readily soluble in methanol and ethanol. Its molecular weight is approximately 666.7 g/mol. The pKa values reflect its acid-base properties, influencing its behavior in different environments. Information on its melting point and other physical characteristics is available in the complete DrugBank entry.

Property	Value
Molecular Formula	C22H30N6O4S
Molecular Weight	666.7 g/mol
Solubility in Water	Slightly Soluble

Pharmacokinetic Considerations

Understanding these properties informs Sildenafil’s absorption, distribution, metabolism, and excretion (ADME) profile. These properties influence dosage regimens and potential drug interactions. Further information regarding Sildenafil’s pharmacokinetics can be found in detailed pharmacodynamic studies.

Mechanism of Action: How Sildenafil Works

Sildenafil’s primary function involves enhancing the effects of nitric oxide (NO). NO, a naturally occurring molecule in the body, relaxes blood vessels, increasing blood flow.

Specifically, Sildenafil inhibits phosphodiesterase-5 (PDE5), an enzyme that breaks down cyclic guanosine monophosphate (cGMP). By inhibiting PDE5, Sildenafil allows cGMP levels to rise. Increased cGMP leads to smooth muscle relaxation in the corpus cavernosum of the penis, facilitating increased blood flow and resulting in an erection.

This mechanism is targeted; Sildenafil’s effects are primarily localized to the penis, reducing the likelihood of widespread vascular effects. However, PDE5 is also found in other areas of the body, such as the lungs and retina, which explains potential side effects like headaches or visual disturbances.

The drug’s efficacy relies on sexual stimulation. Sildenafil doesn’t automatically cause erections; it enhances the body’s natural response to sexual stimulation by improving blood flow to the penis. The duration of action varies, with effects generally lasting several hours.

Important Note: This information is for educational purposes only and does not constitute medical advice. Always consult a healthcare professional before using Sildenafil or any medication.

Therapeutic Uses and Indications of Sildenafil

Sildenafil primarily treats erectile dysfunction (ED) in adult men. It facilitates penile erection by increasing blood flow to the penis. This action is achieved by inhibiting phosphodiesterase type 5 (PDE5), an enzyme that regulates blood vessel dilation.

Beyond ED, sildenafil finds application in pulmonary arterial hypertension (PAH). It improves exercise capacity and reduces symptoms by relaxing blood vessels in the lungs, thereby lowering blood pressure in the pulmonary arteries. This benefit stems from the same PDE5 inhibition mechanism.

Specific dosages vary depending on the condition and individual patient factors. A physician will determine the appropriate dosage and treatment plan. Always follow your doctor’s instructions carefully.

Note: While sildenafil shows promise in other areas of research, these uses are not currently approved by regulatory agencies. Always discuss any potential off-label use with your healthcare provider.

Important Safety Information: Sildenafil carries potential side effects, including headache, flushing, nasal congestion, visual disturbances, and indigestion. Consult a healthcare professional if you experience any adverse reactions or have underlying health conditions, particularly heart problems, before starting sildenafil treatment. Interactions with other medications are possible; full disclosure to your physician of all medications is mandatory.

Common Side Effects and Adverse Reactions

Sildenafil, while generally well-tolerated, can cause several side effects. These are usually mild and temporary, but knowing what to expect can help manage them.

Common Side Effects

• Headache: This is a frequently reported side effect. Staying hydrated and taking pain relievers like acetaminophen can help.
• Facial flushing: A warm, reddened feeling in the face. This usually subsides on its own.
• Indigestion: Some users experience heartburn or upset stomach. Smaller meals and avoiding heavy, fatty foods before taking Sildenafil might help.
• Nasal congestion: A stuffy or runny nose is possible. Saline nasal spray can provide relief.
• Visual disturbances: Changes in color vision (blurred vision, blue tinge) or sensitivity to light are reported. These usually resolve quickly.

Less Common but Important Adverse Reactions

While less frequent, some users experience more serious side effects requiring immediate medical attention:

1. Prolonged erection (priapism): An erection lasting more than four hours needs immediate medical help. This is a rare but serious complication.
2. Sudden vision loss: This is a rare but serious side effect. Stop taking Sildenafil and seek immediate medical attention if this occurs.
3. Sudden hearing loss: Similar to vision loss, this is rare but necessitates immediate medical evaluation and cessation of Sildenafil use.
4. Heart attack or stroke: Individuals with pre-existing heart conditions should discuss Sildenafil use with their doctor. Chest pain, shortness of breath, or other symptoms suggestive of a cardiac event require immediate medical attention.

Remember, this information isn’t a substitute for professional medical advice. Always consult your doctor or pharmacist before starting Sildenafil, especially if you have underlying health conditions or are taking other medications. They can assess your individual risk and provide tailored guidance.

Drug Interactions and Contraindications of Sildenafil

Sildenafil interacts with several medications. Avoid using sildenafil with nitrates (like nitroglycerin) due to a potentially dangerous drop in blood pressure. This combination can cause severe hypotension. Similarly, avoid concurrent use with other PDE5 inhibitors, as this can increase the risk of side effects. Alpha-blockers, often prescribed for hypertension, may also interact with sildenafil, leading to dizziness and low blood pressure. Careful monitoring is necessary if you’re taking alpha-blockers and require sildenafil.

Specific Medications to Avoid

Certain antifungal medications, such as ketoconazole and itraconazole, can increase sildenafil levels in the body, potentially intensifying side effects. Similarly, some HIV protease inhibitors (like ritonavir) may amplify sildenafil’s effects. Avoid using sildenafil with strong CYP3A4 inhibitors due to this potential interaction. Always inform your doctor about all medications, including herbal supplements, you’re taking before starting sildenafil.

Contraindications

Sildenafil is contraindicated in individuals with a history of heart attack or stroke within the last six months. Patients with severe heart conditions or uncontrolled high blood pressure should also avoid it. A history of priapism (prolonged and painful erection) is also a significant contraindication. Individuals with certain rare hereditary eye diseases should consult their physician. Pregnancy and breastfeeding are not relevant contraindications, as sildenafil is not indicated for use in women.