Comparative Evaluation of Oral Melatonin with Midazolam as Premedication for Attenuation of Haemodynamic Responses to Laryngoscopy and Endotracheal Intubation in Adult Elective Surgery Patients Under General Anesthesia

Background: Premedication is used to reduce anxiety, anaesthetic requirements, and hemodynamic fluctuations during laryngoscopy and intubation. Melatonin, when administered orally as premedication before induction of anaesthesia, provides adequate anxiolysis and arousable sedation without impairing cognitive or psychomotor function, along with stable hemodynamics and minimal side effects. Midazolam, a commonly used benzodiazepine, is valued for its rapid onset and short duration of action, and possesses anxiolytic, sedative, hypnotic, and amnesic properties. Comparative data between these agents remains limited.

Methods: This prospective, randomized comparative study included 130 adult patients (18–60 years) undergoing elective surgery under general anaesthesia. Patients received either oral melatonin (6mg) (n = 65) or oral midazolam (7.5mg) (n = 65) 90 minutes before induction. Hemodynamic parameters (HR, SBP, DBP, MBP), Ramsay sedation score, amnesia score, and SpO₂ were recorded at defined intervals (T1–T5).

Results: Both groups showed significant reductions in HR and BP from baseline to 9 minutes post‑intubation. However, melatonin produced significantly lower HR, SBP, DBP, and MBP at key timepoints compared to midazolam (p < 0.05). Sedation scores were higher in the midazolam group, while amnesia scores were lower, indicating greater memory preservation with melatonin. SpO₂ remained stable across groups.

Conclusion: Oral melatonin was more effective than midazolam in attenuating hemodynamic responses to laryngoscopy and intubation, while providing adequate anxiolysis with less sedation and amnesia. These findings support melatonin as a safe and effective alternative premedication in elective surgical patients. Larger multicentre trials are warranted to confirm its role in perioperative care.