What is the CAS number of avanafil?

Introduction to Avanafil

Avanafil is a medication used to treat erectile dysfunction (ED) in men. It belongs to a class of drugs known as phosphodiesterase type 5 (PDE5) inhibitors. This class of medications works by increasing blood flow to the penis during sexual stimulation, which helps to achieve and maintain an erection. Avanafil is known for its rapid onset of action, which can be as quick as 15 minutes in some cases, making it a popular choice for men seeking a fast-acting solution for ED.

Chemical Properties and CAS Number

The Chemical Abstracts Service (CAS) number is a unique numerical identifier assigned to every chemical substance described in the open scientific literature. The CAS number for avanafil is **330784-47-9**. This number is used globally to provide a unique, unmistakable identifier for chemical substances, and it is often used in databases and regulatory documents to ensure clarity and precision.

Mechanism of Action

Avanafil works by inhibiting the enzyme phosphodiesterase type 5 (PDE5). PDE5 is responsible for the breakdown of cyclic guanosine monophosphate (cGMP), a molecule that plays a key role in regulating blood flow in the penis. During sexual stimulation, nitric oxide (NO) is released in the corpus cavernosum of the penis. NO activates the enzyme guanylate cyclase, which increases levels of cGMP. Elevated cGMP levels cause smooth muscle relaxation in the corpus cavernosum, allowing increased blood flow and resulting in an erection. By inhibiting PDE5, avanafil ensures that cGMP levels remain elevated, thereby enhancing the erectile response.

Pharmacokinetics

Absorption

Avanafil is rapidly absorbed after oral administration, with peak plasma concentrations typically reached within 30 to 45 minutes. The absorption of avanafil is not significantly affected by food, which allows for flexibility in dosing relative to meals.

Distribution

Avanafil has a volume of distribution of approximately 21 liters, indicating that it is well-distributed throughout the body. It is highly protein-bound (approximately 99%), which may influence its pharmacokinetics and interactions with other medications.

Metabolism

Avanafil is primarily metabolized by the liver, with the cytochrome P450 enzyme CYP3A4 playing a major role in its biotransformation. The major metabolites of avanafil are inactive, and the drug is excreted primarily in the feces, with a smaller amount excreted in the urine.

Elimination

The elimination half-life of avanafil is approximately 5 hours, which is relatively short compared to other PDE5 inhibitors. This shorter half-life contributes to its rapid onset and shorter duration of action, making it suitable for on-demand use.

Clinical Use and Dosing

Avanafil is typically prescribed for the treatment of erectile dysfunction. The recommended starting dose is 100 mg, taken as needed approximately 15 to 30 minutes before sexual activity. Depending on efficacy and tolerability, the dose may be increased to a maximum of 200 mg or decreased to 50 mg. It is important to note that avanafil should not be taken more than once per day.

Side Effects and Precautions

Like all medications, avanafil can cause side effects. Common side effects include headache, flushing, nasal congestion, and back pain. These side effects are generally mild and transient. However, more serious side effects can occur, including sudden vision loss, hearing loss, and priapism (a prolonged and painful erection). Patients experiencing any of these serious side effects should seek immediate medical attention.

Avanafil should be used with caution in patients with cardiovascular disease, as sexual activity can place an additional strain on the heart. It is also contraindicated in patients taking nitrates or nitric oxide donors, as the combination can lead to a dangerous drop in blood pressure.

Drug Interactions

Avanafil can interact with other medications, potentially leading to adverse effects or reduced efficacy. Notable drug interactions include:

• **Nitrates:** Concomitant use with nitrates can cause severe hypotension.




• **Alpha-blockers:** Co-administration with alpha-blockers can lead to symptomatic hypotension.




• **CYP3A4 inhibitors:** Strong inhibitors of CYP3A4 (e.g., ketoconazole, ritonavir) can increase avanafil plasma levels, necessitating dose adjustments.

Conclusion

Avanafil is a potent and fast-acting PDE5 inhibitor used to treat erectile dysfunction. Its CAS number is 330784-47-9, and it is known for its rapid onset of action and relatively short duration of effect. While generally well-tolerated, it is important for patients to be aware of potential side effects and drug interactions. As with any medication, it should be used under the guidance of a healthcare professional to ensure safety and efficacy.