<p>Absolute Contraindication:</p>

<ul>
	<li>Absence of suitable veins for intravenous administration</li>
	<li>Hypersensitivity (allergy) to barbiturates</li>
	<li>Variegate porphyria (South African) or acute intermittent porphyria</li>
	<li>Status asthmaticus</li>
</ul>

<p>Relative Contraindication:</p>

<ul>
	<li>Severe cardiovascular disease</li>
	<li>Hypotension or shock</li>
	<li>Conditions in which the hypnotic effect may be prolonged or potentiated, eg, excessive premedication, Addison&#39;s disease, hepatic or renal dysfunction, myxedema, increased blood urea, severe anemia, asthma, myasthenia gravis</li>
</ul>