Buspirone effects

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. 

It has been suggested that fluvoxamine inhibifs fhe liver enzymes concerned with the metabolism of buspirone. Concurrent use need not be avoided but it would be wise to remain alert to the possibility of reduced buspirone effects until more is known. 

The pharmacological profile of buspirone in both animals and humans differs substantially from that of the ben2odia2epine anxiolytics. Buspirone lacks anticonvulsant, myorelaxant, and hypnotic effects. It also produces less sedation resulting in less psychomotor impairment in conjunction with... 

The anxiolytic agent buspirone (131) is notable for the fact that it does not interact with the receptor for the benzodiazepines. This difference in biochemical pharmacology is reflected in the fact that buspirone (131) seems to be devoid of some of the characteristic benzodiazepine side effects. The spiran function is apparently not required for anxiolytic activity. Alkylation of 3,3-dimethylglutarimide with dichlorobutane in the presence of strong base yields the intermedi-... 

Anxiolytics are drugs used for the treatment of anxiety disorders. Apart from benzodiazpines, a frequently used anxiolytic is the 5HT1A (serotonin) receptor agonist buspiron, which has no sedative, amnestic or muscle-relaxant side effects, but whose action takes about a week to develop. Furthermore, it is less efficaceous than the benzodiazepines. Buspiron s mechanism of action is not fully understood. 

Some antianxiety drug, such as buspirone (BuSpar), seem to have less abuse potential and less effect on motor ability and cognition than that of Hie other anfianxiety drug. 

However, lorazepam and oxazepam are relatively safe for older adults when given in normal dosages. Buspirone (BuSpar) also is a safe choice for older adults with anxiety because it does not cause excessive sedation, and the risk of falling is not as great. Before bus-pirone therapy is begun, benzodiazepines and sedatives and hypnotics are gradually withdrawn. Buspirone, unlike most of the benzodiazepines, must be taken regularly and is not effective on an as-needed basis. 

The effects of buspirone are decreased when the drug is administered with fluoxetine Increased serum levels of buspirone occur if the drug is taken with erythromycin or itraconazole Should any of these combinations be required, the dosage of buspirone is decreased to 2.5 mg BID, and the patient is monitored closely. Venlafaxine blood levels increase with a risk of toxicity when administered witii MAOIs or cimetidine There is an increased risk of toxicity when trazodone is administered with the phenothiazines and decreased effectiveness of trazodone when it is administered with carbamazepine Increased serum digoxin levels have occurred when digoxin is administered with trazodone There is a risk for increased phenytoin levels when phenytoin is administered witii trazodone... 

Anxiolytics with little abuse potential, such as buspirone, and antidepressants that have a benign side-effect profile and may reduce ethanol intake warrant careful evaluation in the treatment of anxious and depressed alcoholic patients. 

Kranzler HR, Del Boca F, Korner P, et ah Adverse effects limit the usefulness of flu-voxamine for the treatment of alcoholism.] Subst Abuse Treat 10 283-287, 1993 Kranzler HR, Burleson JA, Del Boca FK, et ah Buspirone treatment of anxious alcoholics a placebo-controlled trial. Arch Gen Psychiatry 31 720—731, 1994 Kranzler HR, Burleson JA, Korner P, et ah Placebo-controlled trial of fluoxetine as an adjunct to relapse prevention in alcoholics. Am] Psychiatry 152 391-397, 1995 Kranzler HR, Burleson JA, Brown J, et al Fluoxetine treatment seems to reduce the beneficial effects of cognitive-behavioral therapy in type B alcoholics. Alcohol Clin Exp Res 20 1534-1341, 1996... 

Seppala T, Aranko K, Mattila MJ, et al Effects of alcohol on buspirone and lorazepam actions. Clin Pharmacol Ther 32 201—207, 1982... 

Anxiety disorders are common in the population of opioid-addicted individuals however, treatment studies are lacking. It is uncertain whether the frequency of anxiety disorders contributes to high rates of illicit use of benzodiazepines, which is common in methadone maintenance programs (Ross and Darke 2000). Increased toxicity has been observed when benzodiazepines are co-administered with some opioids (Borron et al. 2002 Caplehorn and Drummer 2002). Although there is an interesting report of clonazepam maintenance treatment for methadone maintenance patients who abuse benzodiazepines, further studies are needed (Bleich et al. 2002). Unfortunately, buspirone, which has low abuse liability, was not effective in an anxiety treatment study in opioid-dependent subjects (McRae et al. 2004). Current clinical practice is to prescribe SSRIs or other antidepressants that have antianxiety actions for these patients. Carefully controlled benzodiazepine prescribing is advocated by some practitioners. 

Ciraulo DA, Sands BE, Shader RI Critical review of liability for benzodiazepine abuse among alcoholics. Am J Psychiatry 145 1501-1506, 1988b Ciraulo DA, Barnhill JG, Ciraulo AM, et al Parental alcoholism as a risk factor in benzodiazepine abuse a pilot smdy. Am J Psychiatry 146 1333-1335, 1989 Ciraulo DA, Antal EJ, Smith RB, et al The relationship of alprazolam dose to steady-state plasma concentrations. J Clin Psychopharmacol 10 27—32, 1990 Ciraulo DA, Sarid-Segal O, Knapp C, et al Liability to alprazolam abuse in daughters of alcoholics. Am J Psychiatry 153 956-958, 1996 Ciraulo DA, Barnhill JG, Ciraulo AM, et al Alterations in pharmacodynamics of anxiolytics in abstinent alcoholic men subjective responses, abuse liability, and electroencephalographic effects of alprazolam, diazepam, and buspirone. J Clin Pharmacol 37 64-73, 1997... 

Importantly, they achieve this without inducing extrapyramidal side-effects or increasing prolactin secretion, which are real problems with neuroleptics. These results have been borne out by preliminary clinical trials of buspirone, used in combination with neuroleptics, and several novel S-HTja agonists (e.g. BSF 190555) are currently under development for this clinical application (Meltzer 1999). 

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. 

Currently, hopes for compounds with greater clinical efficacy and faster onset of action than buspirone rest on the development of selective ligands for 5-HT receptors. So far, antagonists of 5-HT2a/c (e-g- ritanserin), 5-HTs (e.g. ondansetron) and 5-HT4 (e.g. zacopride) receptors have all been explored but their anti-anxiety effects are, at best, equivocal. Full appraisals of the role of 5-HT systems in anxiety and the actions of anti-anxiety drugs are to be found in Handley (1995), Barnes and Sharp (1999) and Olivier, van Wijngaarden and Soudijn (2000). 

Eison, AS, Eison, MS, Stanley, M and Riblet, LA (1986) Serotonergic mechanisms in the behavioural effects of buspirone and gepirone. Pharmac. Biochem. Behav. 24 701-707. 

In addition to the aetions of MDMA and other derivatives at 5-HT2 serotonin reeeptors. some of the effeets on serotonergic systems could be mediated via S-HTja reeeptors, at whieh MDMA has a moderate affinity. Direct agonist effects at this site might eontribute to the mood-altering and calming effects of the drug, sinee similar effects have been reported for novel anxiolyties sueh as ipsaperone and buspirone, which interact with 5-HTia serotonin reeeptors. 

Buspirone generally is well tolerated and does not cause sedation. Most common side effects include dizziness, nausea, and headaches. Drugs that inhibit CYP3A4 (e.g., verapamil, diltiazem, itraconazole, fluvoxamine, nefa-zodone, and erythromycin) can increase buspirone levels. Likewise, enzyme inducers such as rifampin can reduce buspirone levels significantly. Bupirone may increase blood pressure when coadministered with an monoamine oxidase inhibitor (MAOI). 

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