Avanafil, sold under brand names like Stendra and Spedra, is a prescription medication used to treat erectile dysfunction (ED). As a relatively recent development in its class, it provides an alternative for individuals seeking solutions for this common condition. This medication, like its counterparts, is designed to facilitate the ability to achieve and maintain an erection suitable for sexual activity.
Understanding Avanafil’s Mechanism
Avanafil functions as a phosphodiesterase type 5 (PDE5) inhibitor. PDE5 is an enzyme concentrated in the smooth muscle tissues of the penis. Its primary role is to break down a molecule called cyclic guanosine monophosphate (cGMP), which regulates blood flow. By blocking the action of the PDE5 enzyme, avanafil helps maintain higher levels of cGMP.
The process begins with sexual arousal, which triggers the local release of nitric oxide in the penile tissue. This nitric oxide stimulates the production of cGMP, leading to the relaxation of smooth muscles and the dilation of blood vessels. This allows more blood to flow into the sponge-like tissues of the penis, resulting in an erection.
Review of Efficacy and Onset of Action
Clinical studies have consistently demonstrated avanafil’s effectiveness in treating mild to severe erectile dysfunction. Data from trials, including those with challenging patient groups like individuals with diabetes, confirm it significantly improves erectile function compared to a placebo. The medication helps in both achieving an erection and maintaining it for the duration of sexual activity.
A defining characteristic of avanafil is its rapid onset of action. This quick onset is attributed to its pharmacokinetic profile, as it is absorbed rapidly by the body, reaching a maximum concentration in the blood in about 30 to 45 minutes. The duration of its effect can extend beyond six hours, providing a substantial window of opportunity for sexual activity after a single dose.
Comparison with Other ED Treatments
Avanafil’s most notable advantage over sildenafil (Viagra), vardenafil (Levitra), and tadalafil (Cialis) is its rapid onset. While avanafil can take effect in about 15 minutes, sildenafil and vardenafil require 30 to 60 minutes. Tadalafil can take about an hour to begin working, though it is known for its much longer duration of action.
The duration of effect also differs significantly among these medications. Avanafil’s effects last for about six to eight hours. In contrast, sildenafil and vardenafil are effective for up to 12 hours, while tadalafil, often called the “weekend pill,” can remain active for up to 36 hours. This makes tadalafil an option for those who prefer longer-lasting effects.
Avanafil is a second-generation PDE5 inhibitor and exhibits a higher selectivity for the PDE5 enzyme compared to other enzymes in the body. This increased selectivity may contribute to a lower incidence of certain side effects, such as the vision abnormalities less commonly associated with sildenafil. Furthermore, its effectiveness is less likely to be diminished by the consumption of food or moderate amounts of alcohol compared to sildenafil.
Side Effects and Usage Guidelines
The most frequently reported side effects associated with avanafil are generally mild and common across the class of PDE5 inhibitors. These include:
- Headache
- Flushing
- Nasal congestion
- Back pain
More serious side effects are rare but require immediate medical attention, such as an erection lasting longer than four hours (priapism), sudden vision loss in one or both eyes, or a sudden decrease or loss of hearing. Patients are advised to stop taking the medication and seek medical care if they experience these symptoms.
Avanafil is prescribed at a starting dose of 100 mg, to be taken approximately 15 to 30 minutes before sexual activity. Based on the patient’s response and tolerability, the dose may be adjusted. Individuals with certain medical conditions, particularly cardiovascular issues, must consult a doctor, as sexual activity can put a strain on the heart. The medication is contraindicated for individuals taking any form of organic nitrates for chest pain, as the combination can cause a dangerous drop in blood pressure.