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The pharmacokinetics of Nimodipine were studied in healthy volunteers and in patients with subarachnoid hemorrhage (SAH) following cerebral aneurysm rupture. Nimodipine was absorbed rapidly. After an oral dose of 120 mg an average maximal plasma concentration 106 micrograms/l was recorded 45 to 60 minutes later. During a 7-day oral therapy with 40 mg t.i.d. no accumulation or change in the absorption or elimination kinetics occurred. After i.v. administration a biphasic elimination with half lives of 7 min and 1 hour was observed. In patients with subarachnoid hemorrhage receiving a continuous infusion of 2 mg/hour the mean nimodipine plasma concentrations ranged between 36 and 72 micrograms/l. Subsequent oral dose of 60 mg q.i.d. to the same patients resulted in concentrations ranging between 17 to 42 micrograms/l on the average one hour after the dosage. Mean cerebrospinal fluid (CSF) levels amounted to 0.3 +/- 0.2 microgram/l in patients whose mean plasma concentrations were 76.9 +/- 34.0 micrograms/l.

The excretion of azlocillin into the human biliary tract was investigated in 8 patients with a T-tube in the common bile duct after intravenous injection of 2 g. Samples of serum and common duct bile were assayed from 15 min to 12 hours after injection. Biliary tract levels generally run parallel to serum levels but were about 15 times higher than those. Peak levels in T-tube bile averaged 1137 mg/l 60 to 90 min after administration. 12 hours after administration there were still mean concentrations of 13 mg/l to be found. It is concluded that azlocillin concentrations in bile exceed for a long time the minimum inhibitory concentrations for gram-negative and gram-positive causative organisms (above all E. coli, enterococci, Klebsiella spp., Proteus spp., staphylococci) of biliary tract-infections.

Studies on serum and tissue (cutis, muscle and liver) concentrations were carried out with mezlocillin (Baypen), a semi-synthetic new acyl ureidopenicillin, in 51 patients. Serum half life was 59 minutes. The highest concentrations were measured in the cutis, the lowest in the muscles. Concentrations in the liver were found to be relatively constant and persistent.--The efficacy and tolerance of mezlocillin were examined in 48 patients affected by 56 mostly severe infections, which were treated with a dose of 5 g twice or three times daily. The indications for antibiotic treatment were bronchopulmonary infections, peritonitis, soft tissue infections, biliary and urinary tract infections and postoperative febrile conditions of unknown origin. Clinical cure was achieved in 78.5% and an improvement of symptoms in 5.4% of infections. 76% of the causative microorganisms were eliminated. Mezlocillin was locally and systemically well tolerated.

The present studies show that nimodipine prevents and/or improves permanent ischemic neurological deficits in patients with subarachnoid hemorrhage. This was particularly marked in four double-blind, placebo-controlled studies in which statistically significant reductions in mortality and morbidity as consequence of cerebral vasospasm were found. The drug has been shown to increase cerebral blood flow, to reduce vasoconstriction, although not to fully prevent angiographic vasospasm, and to improve central conduction time. Nimodipine did not increase the rate of rebleeding. Its administration during anesthesia does not result in management problems. In general, nimodipine was well tolerated. Side effects were recorded mainly in open studies using the intravenous formulation and consisted mainly of decreases in blood pressure and headaches. Transient increases in liver enzymes may be due to the organic solvent. Hence, all results indicate that patients with subarachnoid hemorrhage will benefit from preventive or therapeutic nimodipine treatment.