Buspirone administration

Like the benzodiazepines, buspirone appears to be safe even when given in very high doses. The most common side effects are dizziness, light-headedness, and headache. Abuse, dependence, and withdrawal have not been reported, and buspirone administration does not produce any cross-tolerance to the benzodiazepines. Buspirone has been reported to increase blood pressure in patients taking monoamine oxidase inhibitors, and it may increase plasma levels of haloperidol if coadministered with that agent. 

Meprobamate causes physical dependence similar to that seen with barbiturate dependence. No physical dependence on buspirone administration has been... 

These observations question the role of noradrenaline as an initiator of anxiety as does the finding that the anti-anxiety drug, buspirone (see Chapter 9), increases the concentration of noradrenaline in the extracellular fluid in the frontal cortex of freely-moving rats (Done and Sharp 1994). Whether this is because buspirone is metabolised to l-(2-pyrimidinyl)-piperazine (1-PP), which is an a2-adrenoceptor antagonist, is uncertain. Unfortunately, no studies have investigated the effects of chronic administration of this drug on noradrenergic transmission this could be important because, unlike benzodiazepines, buspirone is effective therapeutically only after several weeks of treatment. 

Dailey, JW, Mason, K and Stanford, SC (1996) Increased levels of extracellular noradrenaline in the frontal cortex of rats exposed to naturalistic environmental stimuli modulation by acute systemic administration of diazepam or buspirone. Psychopharmacology 127 47-54. 

Monti, J. M., Jantos, H., Silveira, R., Reyes-Parada, M. Scorza, C. (1995a). Sleep and waking in 5,7-DHT-lesioned or (-)-pindolol-pretreated rats after administration of buspirone, ipsapirone, or gepirone. Pharmacol. Biochem. Behav. 52, 305 12. 

Tigel, RD., Uderman, H.D., Shiovitz, T.M., Sramek, J.J., and Cutler, N.R. (2001) Pharmacokinetics and tolerability of buspirone during oral administration to children and adolescents with anxiety disorder and normal healthy adults. / Clin Pharmacol 41 1351-1358. 

Buspirone is available for oral administration in a variety of dosage forms. The usual initial dosage is 7.5 mg twice a day, increased after... 

Absolute bioavailability this implies a comparison of plasma levels after oral and i.v. administration of the drug. Most psychotropic drugs have a good bioavailability, i.e. values between 30 and 100%. Low bioavailabilitv, as seen with buspirone, is associated with highly variable drug plasma concentrations and is not a desirable feature of a drug... 

Other drugs of the depressant, antianxiety, antipyschotic, and anticonvulsive types are being investigated as treatments for cocaine abuse. Those which have been or will be covered in this course include the heterocyclic antidepressants desipramine and imipramine, which diminish cocaine use and craving as well as improve the outcome in the first few months of treatment. Buprenorphine (depressant) may augment the reward system (it has been found to suppress self-administration of cocaine in monkeys). Lithium sometimes works for those who are clinically depressives. Carbamazapine, bromocriptine and mazindol are also used as well as fluphenthixol and buspirone. 

VanderMaelen CP, Matheson GK, Wilderman RC, Patterson LA. Inhibition of serotonergic dorsal raphe neurons by systemic and iontophoretic administration of buspirone, a non-benzodiazepine anxiolytic drug. Eur J Pharmacol 1986 129 123-130. 

Co-administration of erythromycin with the anxiolytic drug buspirone increased the plasma concentration of buspirone (25). 

BUSPIRONE ANXIOLYTICS AND HYPNOTICS-SODIUM OXYBATE Risk of CNS depression - coma, respiratoiy depression Additive depression of CNS Avoid co-administration... 

SODIUM OXYBATE 1. ALCOHOL 2. ANALGESICS - opioids 3. ANTIDEPRESSANTS-TCAs 4. ANTIEPILEPTICS-barbiturates 5. ANTIHISTAMINES 6. ANTIPSYCHOTICS 7. ANXIOLYTICS AND HYPNOTICS-BZDs, buspirone Risk of CNS depression - coma, respiratory depression Additive depression of CNS Avoid co-administration. Caution even with relatively non-sedating antihistamines (cetrizine, desloratidine, fexofenadine, levocetirizine, loratidine, mizolastine) as they can impair the performance of skilled tasks... 

Severe anaphylactic reactions following intravenous administration of diazepam have been reported. Meprobamate causes toxicity similar to that of a barbiturate overdosage. Death may result from respiratory failure or hypotension. Limited information is available about the acute toxicity of Buspirone. Effects are merely extensions of pharmacological effects. Nausea, vomiting, dizziness, drowsiness, miosis, and gastric distention may be seen. 

Dockens, R., Salazar, D.E., Fulmor, I.E., Wehling, M., Arnold, M.E. and Croop, R. (2006) Pharmacokinetics of a newly identified active metabolite of buspirone after administration of buspirone over its therapeutic dose range. Journal of Clinical Pharmacology, 46, 1308-1312. 

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