Which drug is known to suppress adrenal cortisol synthesis as a major risk?

• A. Remifentanil.
• B. Etomidate.
• C. Propofol.
• D. Ketamine.

Answer: (B)

Etomidate has a unique effect on the adrenal glands: it inhibits the enzyme 11-beta-hydroxylase in the adrenal cortex, which is essential for converting rock-bottom precursors into cortisol. Because of this, a single induction dose or an ongoing infusion can markedly reduce cortisol production, especially in patients who are already stressed or critically ill. Cortisol is a key hormone the body uses to mobilize energy, maintain vascular tone, and respond to physiologic stress. When its synthesis is suppressed, patients can develop relative adrenal insufficiency, leading to difficulties in maintaining blood pressure and responding to vasopressors during and after induction.

That’s why etomidate is considered a major risk for adrenal suppression. The other choices do not act by blocking cortisol synthesis through 11-beta-hydroxylase; remifentanil is an opioid with no direct effect on adrenal steroid production, propofol mainly causes hemodynamic changes like low blood pressure without adrenal enzymatic inhibition, and ketamine tends to preserve or even stimulate the stress response rather than suppress cortisol synthesis.