Use of blood monitoring of a drug | PGI MCQs for MD MS Preparations

Use of bloodmonitoring of a drug 

A. For proper therapeutic purpose 
B. For avoiding drug overdose 
C. For increasing drug effectiveness 
D. For shortening drug half life 
E. to calculate the dose of the drug

Ans. A. For proper therapeutic purpose ; (B) For avoiding drug overdose 

Therapeutic drug monitoring is useful in following situations :

----Drugs with safely margin e.g. lithium, digoxin, anticonvulsants, anti-anhythmatics, theophylline, aminoglycoside antibiotics, lithium, tricylic antidepressants.

— Ifindividual variations are large e.g. Li, antidepressants.

— Potentially toxic drugs used in presence of renal failure e.g. aminoglycosides. 

— Poisoning. 

— Failure of response without apparent reason.

   — Compliance

Therapeutic Monitoring is of NO value for :

                ---- Drugs whose response is easily measurable e.g. antihypetensives.

---- Drugs activated in body e.g. levodepa.

---- ‘Hit and run’, drugs (whose effects lasts much longer than the drug itself) e.g., serpine,

---- Drugs with irreversible actions—organophophate anticholine.