Question

For Tiotropium,

1. what are the molecular target for drug, and explain the full mechanism of action (including signalling) for this drug. (at molecule level, cellular level, tissue organ level, over all effects )

• the half life is 24-44 hours
• 2. Calculate how long it takes to eliminate 95% of a single dose of drug from the body. Provide the range of values and the equation used
• 3. From the given pharmacokinetics parameter, explain which elimination model the drug is likely to follow.

Answer 1

1) Molecular target for the drug is the M3 muscuranic receptors common found in lungs.

Mechanism of action

Tiotropium is a muscuranic receptor antagonist, it acts mainly on the M3 muscuranic receptors located on smooth muscle cells and submucosal glands.it leads to contraction of smooth muscle and mucus secretion and produces bronchodilatory effect.

3) Elimination model of the drug

14% of the dose eliminated via urinary excretion and the remaining is mainly non absorbed drug in the gastrointestinal tract which is eliminated via feces.