Local anesthetics have been associated with rare occurrences of sudden respiratory arrest, especially when administered near the head or neck. Convulsions due to systemic toxicity leading to cardiac arrest reported, presumably following unintentional intravascular injection or administration near the head or neck (caution in cardiovascular disease). Caution in hepatic impairment. Caution in acutely ill or debilitated patients. Use with caution in the elderly. Not recommended for use in children <12 years of age. The solution for spinal anesthesia should not be used in children <18 years of age. Do not use solutions containing preservatives for caudal or epidural block. Intravascular injections should be avoided. Use with caution in patients receiving phenothiazines, MAO inhibitors, or TCAs (potential severe hypertension/hypotension). The 0.75% solution is not recommended for obstetrical anesthesia (potential risk of cardiac arrest). Do not inject spinal anesthetics during uterine contractions (spinal fluid current may carry drug further cephalad than desired). Cross-hypersensitivity between amide-type local anesthetics reported. Some epinephrine-containing bupivacaine preparations contain sodium metabisulfite, which may cause allergic-type reactions. Toxic plasma concentrations of local anesthetics (resulting from systemic absorption) associated with adverse CNS effects (e.g. restlessness, anxiety, dizziness, tinnitus, blurred vision, tremors, drowsiness, seizures). Some preparations contain epinephrine (risk of exaggerated vasoconstrictor response in hypertensive vascular disease). Use with caution in areas of the body supplied by end arteries or having otherwise compromised blood supply (e.g. digits, nose, external ear, penis). Many drugs used during the conduct of anesthesia may trigger familial malignant hyperthermia. Conditions that may preclude the use of spinal anesthesia include pre-existing CNS disease, hematological disorders predisposing to coagulopathies, current anticoagulant therapy, chronic backache, preoperative headache, hypotension or hypertension, technical problems (persistent paresthesias, persistent bloody tap), arthritis or spinal deformity, extremes of age, and psychosis or other causes of poor patient cooperation.