Urapidil permeates the intact blood-brain barrier.
OBJECTIVE
To determine the plasma and cerebrospinal fluid (CSF) levels of urapidil after i.v. administration and the effect on CSF serotonin and 5-hydroxyindoleacetic acid (5-HIAA) concentrations.


METHODS
Open, single-dose study.


METHODS
Post-surgery following neurosurgical removal of the hypophysis (n = 5) or aneurysm clipping (n = 1).


METHODS
6 patients, aged 32-71 years, with intact blood-brain barrier (BBB); 1 patient was studied twice.


METHODS
Single dose of 25 mg urapidil i.v. as prophylaxis of BP increase during extubation or as treatment of hypertensive episodes.


RESULTS
Urapidil, serotonin and 5-HIAA were measured by HPLC in CSF during 8 h after urapidil administration. Urapidil was detected in CSF as soon as 5 min after injection in 3 patients. The concentration ratio of plasma/CSF after the distribution phase was about 5:1. No significant effect on serotonin and 5-HIAA in CSF was seen.


CONCLUSIONS
After administration of a therapeutic dose, urapidil permeates the BBB and may interact with central 5-HT1A-receptors.
Castor
G
G
Department of Anaesthesiology, Caritas Hospital, Dillingen/Saar, Germany.
Schmidt
U
U
D000317:Adrenergic alpha-Antagonists / Q000008:administration & dosage / Q000134:cerebrospinal fluid / Q000493:pharmacokinetics*; D000328:Adult; D000368:Aged; D000959:Antihypertensive Agents / Q000008:administration & dosage / Q000134:cerebrospinal fluid / Q000493:pharmacokinetics*; D001812:Blood-Brain Barrier / Q000187:drug effects*; D002851:Chromatography, High Pressure Liquid; D005260:Female; D006801:Humans; D006897:Hydroxyindoleacetic Acid / Q000134:cerebrospinal fluid; D008297:Male; D008875:Middle Aged; D010879:Piperazines / Q000008:administration & dosage / Q000134:cerebrospinal fluid / Q000493:pharmacokinetics*; D012701:Serotonin / Q000134:cerebrospinal fluid; D013997:Time Factors
D000317:Adrenergic alpha-Antagonists; D000959:Antihypertensive Agents; D010879:Piperazines; D012701:Serotonin; D006897:Hydroxyindoleacetic Acid; C015568:urapidil