Caverta tablets are a cheap, effective Male impotence (Erectile Dysfunction) treatment.Caverta is generic Sildenafil Citrate and contains the same ingredients as its more expensive counterpart Viagra produced by Pfizer. Manufactured by company Ranbaxy, Caverta tablets are a distinctive red colour. It takes approximately 45 minutes for Caverta tablets to start working and the pill remains effective for 4-6 hours.