Apomorphine and Viagra (sildenafil) are prescription medications for treating erectile dysfunction (ED). While they both address the same condition, they are not interchangeable and represent two separate approaches to managing ED. Their primary differences lie in how they work within the body, how they are administered, and their potential side effects.
Differing Pathways to a Similar Goal
The core difference between apomorphine and Viagra is their mechanism of action. Apomorphine is a dopamine agonist that works on the central nervous system. It stimulates dopamine receptors in the brain, specifically the hypothalamus, to help regulate sexual desire and arousal. This activation helps initiate the physical response of an erection by influencing the brain’s reward pathways.
Viagra, or sildenafil, is a phosphodiesterase type 5 (PDE5) inhibitor. Instead of affecting brain chemistry, it works directly on the penis by enhancing the effects of nitric oxide, a chemical released during sexual stimulation. This action relaxes the smooth muscles and arteries in the penis, allowing for increased blood flow. Viagra requires sexual stimulation to be effective, as it enhances a natural process rather than initiating arousal in the brain.
Comparing Administration and Timing
The administration of these two medications differs significantly. Apomorphine is formulated as a sublingual tablet designed to dissolve under the tongue for rapid absorption into the bloodstream. In contrast, Viagra is an oral tablet that is swallowed and absorbed through the digestive system.
This difference in administration impacts how quickly each medication takes effect. Sublingual apomorphine has a rapid onset of action, working within 15 to 20 minutes. Oral Viagra takes longer to begin working, between 30 and 60 minutes, as it must be processed by the stomach first.
The duration of the medications’ effects also varies. The effects of apomorphine are shorter-acting, while Viagra remains effective for a longer period, offering a wider window for sexual activity.
Side Effects and Combination Safety
Each medication has a distinct profile of potential side effects. For apomorphine, common adverse events are related to its action on the central nervous system and may include nausea, dizziness, vomiting, and yawning. Some individuals might also experience a temporary change in their sense of taste.
Viagra’s side effects are associated with its impact on blood vessels throughout the body. Common side effects include headache, facial flushing, nasal congestion, and abdominal pain. In some cases, users might experience transient visual changes.
Combining apomorphine and Viagra is not recommended without explicit medical supervision. Taking these medications together can significantly increase the risk of a dangerous drop in blood pressure, a condition known as hypotension. Because both drugs can lower blood pressure through different mechanisms, their combined effect can be more pronounced. A healthcare provider must be consulted to determine the most appropriate treatment.