The analgesic and antipyretic properties of paracetamol were first described in 1893, then it has been widely available as a non-prescription drug, with a therapeutic profile that reflects widespread safety and efficacy as well as paracetamol became the most widely used analgesic and antipyretic in children. It is the most frequently used over-the counter medicine in young children and is nearly universally used in infants. The drug is used by millions of children every day. The study was designed to study the toxicological effect of therapeutic dose of paracetamol after oral administration for three months in laboratory rats (Rattus norvegicous) on the heart, kidney and liver. Results showed oral administration of the paracetamol for three months in laboratory rats showed that this drug has a severe damaging effect on most of the vital organs in the body like kidney, liver and heart.