Mr. Li is 58 years old this year. After retirement, his life has been relatively leisurely, but in recent years he has begun to face a troubling issue – erectile dysfunction. At first, Mr. Li didn’t pay much attention to it, thinking that these problems were inevitable with age. However, when the issue began to affect his quality of life, he had to confront this situation. Following his doctor’s advice, Mr. Li started taking sildenafil, commonly known as “Viagra”.
Initially, Mr. Li strictly followed his doctor’s advice and took sildenafil before meals, and the effects were very good, allowing him to regain his confidence in life. However, one time, due to a gathering with friends, Mr. Li had to take the medication after a meal. As a result, he found that the medication did not seem as effective as before; the onset time was longer, and the results were not as expected. This left Mr. Li very confused.
To figure out the reason for this issue, Mr. Li once again consulted with the hospital. The doctor explained in detail the mechanism of action of sildenafil and pointed out the different effects of taking the medication before and after meals. It turned out that food intake does indeed impact the efficacy of sildenafil, especially high-fat meals. Through this visit, Mr. Li finally understood the relationship between the differences in the efficacy of sildenafil and the timing of taking the medication.
So, is sildenafil more effective when taken before meals or is it better taken after meals? Next, we will provide a detailed answer from the aspects of the drug’s mechanism of action, absorption process, and so on.
1. Pharmacological basis: The mechanism of action and absorption process of sildenafil 1. The basic principle of sildenafil’s action
Sildenafil, as a PDE5 inhibitor, enhances the effect of nitric oxide by inhibiting the activity of phosphodiesterase type 5 (PDE5), promoting the relaxation of the smooth muscle of the corpus cavernosum, thereby increasing blood flow and improving erectile function. In simple terms, it helps men achieve and maintain an erection more easily under sexual stimulation.
Generally, sildenafil begins to take effect within 30 minutes to 1 hour after administration, with a duration of action of about 4 to 6 hours. However, the efficacy of this drug is influenced by various factors, the most significant of which is the process of drug absorption.
2. Absorption and metabolism of sildenafil
Sildenafil is absorbed through the gastrointestinal tract and enters the bloodstream, and its rate and efficiency of absorption directly influence the speed and strength of its efficacy. Food, especially high-fat meals, may delay drug absorption and reduce the intensity of its effect. The drug is metabolized in the liver and primarily eliminated from the body through urine and feces.
There are differences in the metabolic rates among individuals, and furthermore, dietary habits can also affect the drug’s metabolic process. This is why
