Thiopental Sodium

What it is used for

• Anesthesia
• Anesthesia
• Anesthesia
• Anesthesia (unpremedicated)
• Anesthesia (after tranquilization)
• Anesthesia (after narcotic premedication)
• Anesthesia induction
• Anesthesia
• Deep surgical anesthesia (unweaned calves fasted 6-12h)
• Anesthesia (calves under 2 weeks of age)
• Anesthesia (after sedation and guaifenesin)
• Anesthesia (after tranquilization)
• Anesthesia (with preanesthetic tranquilization)

How it is given

Possible side effects

• Ventricular bigeminy (dogs)
• Apnea (especially in cats)
• Arterial hypotension
• Excitement and severe ataxia during recovery (horses, if used alone)
• Transient leukopenia and hyperglycemia (horses)
• Vascular dilatation and hypoglycemia (with rapid IV administration)
• Severe tissue necrosis (if administered perivascularly)
• Prolonged recovery with repeated doses

Cautions & contraindications

• Absence of suitable veins for IV administration (Absolute)
• History of hypersensitivity to barbiturates (Absolute)
• Status asthmaticus (Absolute)
• Preexisting leukopenia in horses
• Use with extreme caution or avoid in greyhounds and other sight hounds
• Relative: Severe cardiovascular disease, ventricular arrhythmias, shock, increased intracranial pressure, myasthenia gravis, severe hepatic disease
• > **WARNING:** Thiopental is highly alkaline. Extravasation and intra-arterial injections must be strictly avoided to prevent severe tissue necrosis and CNS toxicity. * **Sight Hounds:** Greyhounds metabolize thiobarbiturates much more slowly; prolonged recoveries are common. Consider alternatives. * **Administration:** Give strictly to effect. Repeated doses accumulate and significantly prolong recovery. * **Dilution:** Do not use concentrations less than 2% in sterile water as they may cause hemolysis. * **Pregnancy:** Readily crosses the placental barrier; use with caution (FDA Category C).

Drug interactions

• Clonidine: IV clonidine prior to induction may reduce thiopental dosage requirements by up to 37%
• CNS Depressants: May enhance respiratory and CNS depressant effects
• Diazoxide: Potential for hypotension
• Epinephrine / Norepinephrine: Ventricular fibrillatory effects may be potentiated when used with thiobarbiturates and halothane
• Metoclopramide: Given prior to induction may reduce thiopental dosage requirements
• Midazolam: May potentiate hypnotic effects
• Opiates: Given prior to induction may reduce thiopental dosage requirements
• Phenothiazines: May potentiate thiopental effects; hypotension possible
• Probenecid: May displace thiopental from plasma proteins
• Sulfonamides: Thiopental and sulfas may displace one another from plasma proteins

Frequently asked questions