Therapeutic Drug Monitoring

Question 0

When is TDM indicated

Answer 0

Patient - lack of response, adherence, suspected toxicity

Co-morbidities - drug interactions, renal/hepatic, GI probs

Special populations

Question 1

Which drugs require TDM

Answer 1

Lithium, TCAs
Neuroleptics (phenytoin and phenobarbital)
Few antibiotics (gent, vanc, amikacin)
Digoxin
Immunosuppressives

Question 2

Causes of low drug concentration

Answer 2

Incorrect dose
Patient non-compliance
Rapid elimination
Timing of sample collection

Question 4

Causes of high drug concentration

Answer 4

Error in dose
Decreased renal/hepatic function
Slow elimination
Timing of sample collection (soon after administration)