Question 87

Therapeutic duplication would be a concern for a patient prescribed both tamsulosin and doxazosin.

Tamsulosin and doxazosin are both alpha-1 adrenergic antagonists used to treat conditions like benign prostatic hyperplasia (BPH). Prescribing both together may lead to increased side effects or exacerbation of hypotension due to their similar mechanisms of action.

A) doxazosin

Doxazosin is an alpha-1 blocker, just like tamsulosin. When used together, they can increase the risk of adverse effects such as low blood pressure and dizziness. This overlap in therapeutic action raises concerns about therapeutic duplication, making this option correct.

B) guaifenesin

Guaifenesin is an expectorant used to relieve chest congestion and does not share a therapeutic class with tamsulosin. Therefore, there is no concern for therapeutic duplication when these two medications are prescribed together, making this option incorrect.

C) tamoxifen

Tamoxifen is a selective estrogen receptor modulator primarily used in breast cancer treatment. It does not have a pharmacological overlap with tamsulosin, thus posing no risk of therapeutic duplication. Therefore, this option is incorrect.

D) baclofen

Baclofen is a muscle relaxant used to treat spasticity and does not overlap with the action of tamsulosin. There is no therapeutic duplication concern with this medication, rendering this option incorrect.

Conclusion

The correct answer is doxazosin due to its similar pharmacological effects as tamsulosin, which raises the risk of therapeutic duplication. All other options do not share mechanisms of action with tamsulosin, thereby eliminating concerns of therapeutic duplication when combined with it.