The two main COMTinhibitory drugs tolcapone Tasmar and entac

The two main COMT-inhibitory drugs tolcapone (Tasmar) and entacapone:

A. enhance central COMT but not in the PNS.

B. enhance COMT in both the PNS and CNS.

C. have no effect on COMT in either the PNS nor CNS.

D. inhibit peripheral COMT but not in the CNS.

Solution

Answer : B

Catechol-O-methyl transferase ( COMT ) inhibitory drugs:

Tolcapone (Tasmar ) :

Chemical formula : C₁₄H₁₁NO₅

Mode of action : It has ability to cross the blood-brain barrier and thus exerts COMT inhibitory effects in the CNS as well as pheriphery nervous system.

Entacapone :

Chemical formula : C₁₄H₁₅N₃0₅

Mode of action : COMT inhibitory effects in CNS and PNS

Both drugs are used parkinson diseases, block an enzymes that metabolizes dopamine and boost effects of levodopa and dopamine.