Sildenafil citrate, the active component of Kamagra tablets, is a member of the group of drugs called phosphodiesterase type 5 (PDE5) inhibitors. 
Women should not take Kamagra tablets, and males should see a doctor before taking any other medications to cure impotence.  When used alongside medications known as nitrates, which are frequently prescribed for angina or chest discomfort, it may be harmful.  If you have low blood pressure, have recently experienced a heart attack or stroke, or have serious liver or heart issues, do not use this medication.