- Methohexital should be administered only in hospital or ambulatory care settings with continuous monitoring of respiratory and cardiac function [US Black Box Warning]
- Ensure maintenance of a patent airway and adequacy of ventilation during induction and maintenance of anesthesia, as laryngospasm due to a combination of secretions and accentuated reflexes following induction or from painful stimuli during light anesthesia can occur
- Seizures have been reported in patients with a previous history of convulsive activity, especially partial seizure disorders. Hence use cautiously in these patients
- Prefer another induction agent in patients with severe hepatic dysfunction, severe cardiovascular instability, or a shock-like condition as liver is involved in metabolism of methohexital and as barbiturates enhance preexisting circulatory depression
- Cumulative effects, including extended somnolence, protracted unconsciousness, and respiratory and cardiovascular depression has been reported with prolong use. Respiratory depression in the presence of an impaired airway can lead to hypoxia, cardiac arrest, and death
- Unintended intra-arterial injection of barbiturate produces platelet aggregates and thrombosis in arterioles distal to the site of injection resulting in to necrosis and gangrene. If patients complain fiery burning following the distribution path of the injected artery, immediately stop the injection and reevaluate the situation
- Administration of methohexital sodium can produce hiccups, coughing, and laryngospasm, which may impair pulmonary ventilation
- Temporary hypotension and tachycardia can occur following the induction
- Recovery from methohexital anesthesia is rapid and smooth
Cautions: Use cautiously in
- Renal impairment
- Hepatic impairment
- Asthma
- Obstructive pulmonary disease
- Severe hypertension or hypotension
- Myocardial disease
- Congestive heart failure
- Severe anemia
- Extreme obesity
- Debilitated patients
- Endocrine diseases
- Circulatory disorder
- Respiratory disorder
- Seizure disorder
Pregnancy Category:B
Breastfeeding: Very small amount of methohexital is excreted in milk. No waiting period is required; mother can resume breast feeding as soon as she recovered sufficiently to nurse. Follow the recommendations for the most problematic medication when combination of anesthetic agents is used for the procedure. This information is based upon LactMed database (available at http://toxnet.nlm.nih.gov/cgi-bin/sis/htmlgen?LACT last accessed 27 May 2011). Manufacturer advises caution.
