What type of kinetics applies to alcohol in the body? Explain the clinical significance.

There are two processes involved in alcohol metabolism: Alcohol Dehydrogenase (AD) and MEOS (Mixed Function Oxidases).

Alcohol dehydrogenase is typically the metabolism seen when smaller amounts of alcohol are consumed. It is a zero-order kinetic process, which means the enzymes can become saturated. This process catalyzes the conversion of alcohol to acetaldehyde

MEOS is the system that steps in when larger amounts of alcohol are consumed. It induces the enzyme system to produce more enzymes to metabolize the large amounts of alcohol that is consumed, which means more alcohol per time unit can be broken down.

Summary of the metabolic pathway of ethanol metabolism

The end product of alcohol metabolism is acetaldehyde, which is converted to CO2 and H2O to be excreted from the body. The alcohol is metabolised in the liver by the enzymes Aldehyde dehydrogenase and also dependent on the coenzyme NAD.

Which drugs affect metabolism, and what are the effects?

Drugs like Disulfiram, Metronidazole, Cephalosporins, and Hypoglycemics interfere with the metabolism by inhibiting the Aldehyde dehydrogenase enzyme. This inhibition leads to the build-up of acetaldehyde in the body resulting in side effects such as nausea, vomiting, headaches.