The clinical pharmacokinetics of buflomedil in normal subjects after intravenous and oral administration

A fatal case of buflomedil self-poisoning: toxicological data and literature review

A fatal case of buflomedil (Fonzylane) self-poisoning is presented. Drug identification and quantification in postmortem blood, urine and gastric contents was achieved by means of high pressure liquid chromatography with diode-array detection (HPLC/DAD). Blood concentration was 275 micrograms/ml, > 70 times the usual therapeutic values. Toxicological results are discussed in the light of the existing literature.

Evaluation of two buflomedil tablet formulations in patients with atherosclerotic disease

The bioequivalence of a 600-mg methocel tablet containing buflomedil hydrochloride in sustained-release form was determined relative to a 300-mg CAP/carbovax-coated tablet of buflomedil hydrochloride in immediate-release form. The tablets were given to 20 patients in a double-blind placebo-controlled clinical study with cross-over between the administration plans. The 300-mg tablets were given b.i.d., at 8 a.m. and 8 p.m. while the 600-mg tablets were taken once a day at 8 a.m. (+placebo at 8 p.m.). Plasma samples were collected at appropriate times up to 24 h after administration and were analyzed for buflomedil with a validated high-performance liquid chromatographic procedure. Results showed an overall significant mean difference in absorption rate between the two formulations. The mean tmax (5.5 +/- 3.5 h) for the 600-mg tablet was longer (P < 0.001) than the tmax value (1.8 +/- 0.8 h) seen after administration of the first 300-mg tablet. Analysis of AUC(O-infinity) values indicated that the sustained-release preparation (32.1 +/- 20.7 micrograms/ml h) was not significantly different from the 300-mg tablet b.i.d. (28.7 +/- 16.0 micrograms/ml h). Furthermore, it was seen that single administration of a 600-mg sustained-release tablet of buflomedil hydrochloride delivered the same amount of total drug as a 300-mg tablet given twice a day.

Acute buflomedil intoxication: a life-threatening condition

A 15-year-old girl was admitted to ICU in a comatose state. She presented with mydriasis, areflexia, hypoxemia and seizures. She was immediately intubated and connected to a ventilator. The seizures were reversed with intravenous diazepam. CT scan was negative. EEG showed a diffuse fast activity and theta waves with spikes in the anterior and temporal regions, bilaterally. The gastric lavage was suggestive of drug ingestion. The patient completely recovered after 6 h of mechanical ventilation and supportive management. Mydriasis was still present after the resolution of neurological symptoms. The girl told us she had ingested 10 tablets (3 g-55 mg/kg) of Loftyl (buflomedil) for suicidal intention. The buflomedil concentrations at 2-3 h from ingestion were 24.8 mg/l in the blood, 324.4 mg/l in the urine and 6.9 mg/l in the gastric content. The p-desmethyl metabolite was also identified in the urine. Buflomedil is a rheological agent largely used as a vasodilator in some European countries. Some recent reports have emphasized the risk of acute intoxication with this drug. Relatively low doses (50-60 mg/kg) have been associated with an important neurological toxicity and a high mortality. We suggest that the clinical picture we observed might be related to a neuroleptic-type action of buflomedil. We bring to attention the risk of a large, uncontrolled diffusion of a drug capable to cause serious consequences at relatively low doses.

An evaluation of the ability of the peripheral vasodilator buflomedil to improve vascular patency after acute frostbite

The extent of microvascular damage from frostbite can be accurately demonstrated by vascular microcorrosion casting techniques (P. S. Daum, W. D. Bowers, Jr., J. Tejada, and M. P. Hamlet, Cryobiology 24, 65-73, 1987). In the present investigation, the peripheral vasodilator buflomedil was evaluated for its ability to ameliorate microcirculatory damage from acute experimentally induced freeze injury. This drug has been reported to decrease tissue loss in human frostbite patients when given intravenously during thawing (J. Foray, P. E. Baisse, J. P. Mont, and Cl. Cahen, Sem. Hop. Paris 56, 490-497, 1980). In seven groups of anesthetized rats, left hindpaws were cooled to heat of fusion; cooling continued until the temperature in the footpads fell to -15 degrees C. Prior to cooling, group 1 received a tail vein injection of 1 ml saline/kg, while group 2 received 10 mg buflomedil/kg. Immediately following cooling, group 3 received an injection of 10 mg buflomedil/kg. Hindpaws were rapidly rewarmed in a 40 degree C bath. During rewarming, left hindpaws from group 4 were immersed in deionized water, from group 5 in 24 mg buflomedil in deionized water, from group 6 in 30% dimethyl sulfoxide (Me2SO), and from group 7 in 24 mg buflomedil in 30% Me2SO. Right hindpaws served as controls. Vascular microcorrosion casts were made from left and right hindpaws of all groups. There was no significant difference in mean cast weights when frozen hindpaws of the seven groups were compared, although treatment with buflomedil increased the mean cast weight of control hindpaws from groups 3 and 7. It therefore appears that, in this acute model for frostbite, buflomedil does not improve vascular patency.

Clearance studies of methotrexate and 7-hydroxy-methotrexate in rabbits after multiple-dose infusion

The concentration-dependent clearance of methotrexate (MTX) and its metabolite, 7-hydroxy-methotrexate (7-OH-MTX), was demonstrated in 5 rabbits using 7 infusion rates (10.5-323 mg/hr). Mean total body clearance (from 34.3 to 13.1 ml/min) and mean renal clearance (from 25.6 to 7.6 ml/min) of MTX were found to decrease with increasing steady-state plasma concentrations (from 5.1 to 412 micrograms/ml), whereas nonrenal clearances remained relatively constant. An essentially steady-state plasma level of 7-OH-MTX was achieved during each MTX infusion, and its renal clearance also decreased (from 37.3 to 6.5 ml/min) with increasing metabolite levels (from 1.8 to 293 micrograms/ml). Saturable renal tubular secretion appeared operative for both drug and metabolite since their renal clearance (based on the free drug) to inulin clearance ratios were much greater than unity and the ratios were markedly reduced in 2 rabbits after probenecid treatment. Plasma protein binding of MTX (56%) and 7-OH-MTX (49%) were independent of concentrations between 0.1 and 300 micrograms/ml. Negligible MTX metabolism was found in rabbit kidney homogenates, thus validating renal clearance measurement in the present study.