Sildenafil Citrate 50MG Sildenafil belongs to a class of chemicals known as PDE5 inhibitors. c-GMP-specific phosphodiesterase type 5 is found primarily in the corpus cavernosum area of the penis and in the retina. Buy Sildenafil Citrate WARNING This product is a very potent chemical. This product is NOT for human use and can be harmful if ingested. This product is for research/laboratory use only. This product is NOT in a sterile solution and is NOT to be injected. This product should only be handled by licensed, qualified professionals. This product is not a drug, food, or cosmetic and should not be misbranded, misused or mislabeled as a drug, food or cosmetic. The latter article is intended for educational / informational purposes only. THIS PRODUCT IS INTENDED AS A RESEARCH CHEMICAL ONLY. This designation allows the use of research chemicals strictly for in vitro testing and laboratory experimentation only. Bodily introduction of any kind into humans or animals is strictly forbidden by law