The administration of local anesthetic solutions containing epinephrine or norepinephrine to patients receiving monoamine oxidase inhibitors, tricyclic antidepressants or phenothiazines may produce severe, prolonged hypotension or hypertension.
Concurrent use of these agents should generally be avoided.
In situations when concurrent therapy is necessary, careful patient monitoring is essential.Concurrent administration of vasopressor drugs (for the treatment of hypotension related to obstetric blocks) and ergot-type oxytocic drugs may cause severe, persistent hypertension or cerebrovascular accidents.The para-aminobenzoic acid metabolite of chloroprocaine inhibits the action of sulfonamides.Therefore, chloroprocaine should not be used in any condition in which a sulfonamide drug is being employed.
Nesacaine 1% and 2% Injections, in multidose vials with methylparaben as preservative, are indicated for the production of local anesthesia by infiltration and peripheral nerve block.They are not to be used for lumbar or caudal epidural anesthesia.Nesacaine-MPF 2% and 3% Injections, in single dose vials without preservative and without EDTA, are indicated for the production of local anesthesia by infiltration, peripheral and central nerve block, including lumbar and caudal epidural blocks.Nesacaine and Nesacaine-MPF Injections are not to be used for subarachnoid administration.
LOCAL ANESTHETICS SHOULD ONLY BE EMPLOYED BY CLINICIANS WHO ARE WELL VERSED IN DIAGNOSIS AND MANAGEMENT OF DOSE RELATED TOXICITY AND OTHER ACUTE EMERGENCIES WHICH MIGHT ARISE FROM THE BLOCK TO BE EMPLOYED, AND THEN ONLY AFTER ENSURING THE IMMEDIATE AVAILABILITY OF OXYGEN, OTHER RESUSCITATIVE DRUGS, CARDIOPULMONARY RESUSCITATIVE EQUIPMENT, AND THE PERSONNEL RESOURCES NEEDED FOR PROPER MANAGEMENT OF TOXIC REACTIONS AND RELATED EMERGENCIES (see also ADVERSE REACTIONS and PRECAUTIONS).
DELAY IN PROPER MANAGEMENT OF DOSE RELATED TOXICITY, UNDERVENTILATION FROM ANY CAUSE AND/OR ALTERED SENSITIVITY MAY LEAD TO THE DEVELOPMENT OF ACIDOSIS, CARDIAC ARREST AND, POSSIBLY, DEATH.
NESACAINE (chloroprocaine HCl Injection, USP) contains methylparaben and should not be used for lumbar or caudal epidural anesthesia because safety of this antimicrobial preservative has not been established with regard to intrathecal injection, either intentional or unintentional.NESACAINE-MPF Injection contains no preservative; discard unused injection remaining in vial after initial use.Vasopressors should not be used in the presence of ergot-type oxytocic drugs, since a severe persistent hypertension may occur.To avoid intravascular injection, aspiration should be performed before the anesthetic solution is injected.
The needle must be repositioned until no blood return can be elicited.
However, the absence of blood in the syringe does not guarantee that intravascular injection has been avoided.Mixtures of local anesthetics are sometimes employed to compensate for the slower onset of one drug and the shorter duration of action of the second drug.
Experiments in primates suggest that toxicity is probably additive when mixtures of local anesthetics are employed, but some experiments in rodents suggest synergism.Caution regarding toxic equivalence should be exercised when mixtures of local anesthetics are employed.