Kamagra Effervescent is a medication that contains sildenafil citrate as its active ingredient. Sildenafil is a phosphodiesterase type 5 (PDE5) inhibitor, and it is commonly used to treat erectile dysfunction (ED). Kamagra is a brand that offers various formulations of sildenafil, and the effervescent form comes in a dissolvable tablet that is mixed with water before consumption.