Biotransformation into inactive product
Example: procaine is used for dental procedures and is metabolized locally by the enzyme pseudo-cholinesterase (hydrolysis). The result is two inactive compounds.
- Preparation for elimination
Example: paracetamol is metabolized primarily in the liver, where it undergoes conjugation with sulphate and glucuronide. The result is two inactive polar compounds ready for renal elimination.
Biotransformation into active product
Example: sulindac is an inactive compound that converted by liver enzymes to a sulphide. The result is an active NSAID.
- Active metabolites
Example: imipramine is a tricyclic antidepressant that is oxidized by microsomal enzymes in the liver to desipramine. The result is an equally effective tricyclic antidepressant.