Paracetamol + Tramadol Hydrochloride

Paracetamol relieves pain and reduces fever, with only mild anti-inflammatory effect. It is thought to work mainly within the central nervous system (CNS), raising the pain threshold by inhibiting the COX-1, COX-2, and COX-3 enzyme isoforms involved in prostaglandin (PG) synthesis. Paracetamol, a para-aminophenol derivative also known as acetaminophen, is among the most widely used, safest, and fastest-acting pain relievers available, and it is well tolerated, avoiding the various side effects associated with aspirin.

Tramadol, for its part, is a centrally acting synthetic opioid painkiller. Its exact mode of action is not fully understood, but animal studies point to at least two complementary mechanisms: the binding of tramadol itself and its M1 metabolite to μ-opioid receptors, and a weak inhibition of norepinephrine and serotonin reuptake. Its opioid activity stems from both the low-affinity binding of the parent compound and the higher-affinity binding of the O-demethylated M1 metabolite to μ-opioid receptors. Tramadol has also been shown, in vitro, to inhibit reuptake of norepinephrine and serotonin, as do some other opioid analgesics. Together, these mechanisms are thought to contribute independently to tramadol's overall pain-relieving effect.