This Article Full Text Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Email this article to a colleague Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Request Permissions Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Naguib, M. Articles by Alharby, S. W. Search for Related Content PubMed PubMed Citation Articles by Naguib, M. Articles by Alharby, S. W. Related Collections Pharmacology

---

ANESTHETIC PHARMACOLOGY

The Effects of Melatonin Premedication on Propofol and Thiopental Induction Dose–Response Curves: A Prospective, Randomized, Double-Blind Study

Mohamed Naguib, MB, BCh, MSc, FFARCSI, MD^*, Abdulhamid H. Samarkandi, MB, BS, KSUF, FFARCSI, Mohamed A. Moniem, MD, Emad El-Din Mansour, MD, Ahmad A. Alshaer, MD, Hasan A. Al-Ayyaf, MB, BCh, Awatif Fadin, MB, BCh, and Saleh W. Alharby, MB, BS, FRCS (Glas)

From the *Department of Anesthesiology and Pain Medicine, The University of Texas M. D. Anderson Cancer Center, Houston, Texas; and Departments of Anesthesia and Surgery, King Saud University, Riyadh, Saudi Arabia.

Address correspondence and reprint requests to Mohamed Naguib, MB, BCh, MSc, FFARCSI, MD, Department of Anesthesiology and Pain Medicine, University of Texas M.D. Anderson Cancer Center, Unit 409, 1400 Holcombe Boulevard, Houston, TX 77030. Address e-mail to naguib{at}mdanderson.org.

BACKGROUND: The effect of melatonin on the intraoperative requirements for IV anesthetics has not been documented. We studied the effect of melatonin premedication on the propofol and thiopental dose–response curves for abolition of responses to verbal commands and eyelash stimulation.

METHODS: This prospective, randomized, double-blind study included 200 adults with ASA physical status I. Patients received either 0.2 mg/kg melatonin or a placebo orally for premedication (n = 100 per group). Approximately 50 min later, subgroups of 10 melatonin and 10 placebo patients were administered various doses of propofol (0.5, 1.0, 1.5, 2.0, or 2.4 mg/kg) or thiopental (2.0, 3.0, 4.0, 5.0, or 6.0 mg/kg) for anesthetic induction. The ability of each patient to respond to the command, "open your eyes," and the disappearance of the eyelash reflex were assessed 60 s after the end of the injection of propofol or thiopental. Dose–response curves were determined by probit analysis.

RESULTS: Melatonin premedication decreased thiopental ED₅₀ values for loss of response to verbal command and eyelash reflex from 3.4 mg/kg (95%confidence interval, 3.2–3.5 mg/kg) and 3.7 mg/kg (3.5–3.9 mg/kg) to 2.7 mg/kg (2.6–2.9 mg/kg) and 2.6 mg/kg (2.5–2.7 mg/kg), respectively (P < 0.05). Corresponding propofol ED₅₀ values decreased from 1.5 mg/kg (1.4–1.6 mg/kg) and 1.6 mg/kg (1.5–1.7 mg/kg) to 0.9 mg/kg (0.8–0.96 mg/kg) and 0.9 mg/kg (0.8–0.95 mg/kg), respectively (P < 0.05).

CONCLUSIONS: Melatonin premedication significantly decreased the doses of both propofol and thiopental required to induce anesthesia.

This article has been cited by other articles:

				M. Naguib and P. A. Goldstein All Results Count Anesth. Analg., April 1, 2009; 108(4): 1058 - 1061. [Full Text] [PDF]

				S. A. Ismail and H. A. Mowafi Melatonin Provides Anxiolysis, Enhances Analgesia, Decreases Intraocular Pressure, and Promotes Better Operating Conditions During Cataract Surgery Under Topical Anesthesia Anesth. Analg., April 1, 2009; 108(4): 1146 - 1151. [Abstract] [Full Text] [PDF]