Drug interactions buspirone

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. 

Concomitant therapy When buspirone is to be given with a potent inhibitor of CYP3A4, the dosage recommendations described in the Drug Interactions section should be followed. 

Buspirone tends to be used preferentially in patients with chronic and persistent anxiety, in patients with comorbid substance abuse, and in elderly patients, because it is well tolerated and has no significant pharmacokinetic drug interactions. What is clear is that buspirone shows reproducible efficacy in certain animal models of anxiety and in GAD, which points to a potentially important role of serotonin in mediating anxiety symptoms through 5HT1A receptors. Buspirone also has a role as an augmenting agent for the treatment of resistant depression, as discussed in Chapter 7. 

MDMA DRUG DEPENDENCE THERAPIES-BUSPIRONE Markedly t risk of serotonin syndrome Buspirone is a direct stimulant of 5-HT receptors (5-HT1A) Avoid concomitant use - For signs and symptoms of serotonin toxicity, see Qinical Features of Some Adverse Drug Interactions, Serotonin toxicity and serotonin syndrome... 

Buspirone is a well-tolerated drug, the most commonly reported side effects being transient dizziness, light-headedness, headache, and gastrointestinal disturbances. Other limitations of buspirone are its delayed onset of action (fewday s to a few weeks) and a significant drug interaction with MAOIs. 

Additive CNS depression This occurs when sedative-hypnotics are used with other drugs in the class as well as with alcoholic beverages, antihistamines, antipsychotic drugs, opioid analgesics, and tricyclic antidepressants. This is the most common type of drug interaction involving sedative-hypnotics. Additive CNS depression with buspirone is uncommon. 

Other adverse effects Barbiturates and carbamates (but not benzodiazepines, buspirone, zolpidem, or zaleplon) induce the formation of the liver microsomal enzymes that metabolize dmgs. This enzyme induction may lead to multiple drug interactions. Barbiturates may also precipitate acute intermittent porphyria in susceptible patients. Chloral hydrate may displace coumarins from plasma protein binding sites and increase anticoagulant effects. 

Drug/Food interactions The bioavailability of buspirone is increased when given with food as compared with the fasted state. 

Drugs that may interact with rifabutin include the following Anticoagulants, azole antifungal agents, benzodiazepines, beta blockers, buspirone, corticosteroids, cyclosporine, delavirdine, doxycycline, hydantoins, indinavir, rifamycins, losartan, macrolide antibiotics, methadone, morphine, nelfinavir, quinine, quinidine, theophylline, aminophylline, tricyclic antidepressants, and zolpidem. 

Buspirone is well-tolerated, with the main side-effects being dizziness, anxiety, nausea and headache. It is tolerated by the elderly (Bohm et al. 1990). It does not cause sexual dysfunction and does not appear to be associated with a discontinuation syndrome. Overdose causes drowsiness but there are no reports of serious toxic effects. A potential for interaction with drugs that inhibit the CYP450 3A4 isoenzyme is not a significant problem in cHnical practice. GAD is usually a chronic condition and buspirone is suitable for long-term treatment. Patients should be advised to expect a slow onset of benefits and be reviewed regularly in the early stages of treatment. 

Buspirone has selective anxiolytic effects, and its pharmacologic characteristics are different from those of other drugs described in this chapter. Buspirone relieves anxiety without causing marked sedative, hypnotic, or euphoric effects. Unlike benzodiazepines, the drug has no anticonvulsant or muscle relaxant properties. Buspirone does not interact directly with GABAergic systems. It may exert its anxiolytic effects by acting as a partial agonist at brain 5-HTia receptors, but it also has affinity for brain dopamine D2 receptors. Buspirone-treated patients show no... 

Buspirone Mechanism uncertain Partial agonist at 5-HT receptors but affinity for D2 receptors also possible Slow onset (1-2 weeks) of anxiolytic effects t minimal psychomotor impairment—no additive CNS depression with sedative-hypnotic drugs Generalized anxiety states Oral activity forms active metabolite short half-life Toxicity Tachycardia paresthesias t gastrointestinal distress Interactions CYP3A4 inducers and inhibitors... 

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