[Pharmacotoxicologic characteristics of pentacaine]

Long-term administration of pentacaine to experimental animals in investigations of chronic toxicities confirmed that this substance is relatively safe in amounts of 10 mg/kg/day. Larger doses caused ECG changes, as well as changes of some clinical and biochemical indicators and histopathological findings which were independent on the dose and sex. The embryotoxic and teratogenic action of pentacaine was manifested only after large doses in mice (more than 20 mg/kg). Doses under 10 mg/kg per day did not produce toxic effects in mother and foetus, whereby the substance penetrates through the placenta and is distributed in the maternal and foetal organs of rabbits in a proportionate way. From the in vitro action of pentacaine ensues that it has a strong stimulating action on isolated cells which gradually changes into cytotoxic action. The results support the decision not to use pentacaine for intravenous, infiltration and conduction anaesthesia and to recommend only its oral administration.