Question 34

Tacrolimus is known to have a narrow therapeutic index.

Tacrolimus is a medication that requires careful monitoring due to its narrow therapeutic index, meaning the difference between the minimum effective dose and the minimum toxic dose is small.

A) Tacrolimus

This option is correct as tacrolimus is well-documented to have a narrow therapeutic index. It is an immunosuppressant used primarily in organ transplant patients, where precise dosing is crucial to avoid toxicity and ensure efficacy.

B) Tolterodine

Tolterodine does not have a narrow therapeutic index. It is an anticholinergic medication used primarily for the treatment of overactive bladder, and its dosing does not require the same level of precision as tacrolimus.

C) Travoprost

Travoprost is an ophthalmic solution used to lower intraocular pressure in patients with glaucoma. It does not exhibit a narrow therapeutic index, as its therapeutic range is wider compared to tacrolimus.

D) Tadalafil

Tadalafil, used for erectile dysfunction and pulmonary arterial hypertension, also does not have a narrow therapeutic index. Its dosing is more flexible and does not pose the same risks associated with narrow therapeutic index medications.

Conclusion

Tacrolimus is the only medication listed that is characterized by a narrow therapeutic index, necessitating careful monitoring to avoid adverse effects. The other options, while important medications, do not share this critical pharmacological characteristic, which underscores the significance of tacrolimus in clinical settings.