Buspirone Hydrochloride 7.5 mg Tablet, 100-count — NDC 64980-651-01 (Billing 64980-0651-01)

WARNINGS The administration of buspirone hydrochloride tablets to a patient taking a monoamine oxidase inhibitor (MAOI) may pose a hazard . There have been reports of the occurrence of elevated blood pressure when buspirone hydrochloride tablets have been added to a regimen including an MAOI. Therefore, it is recommended that buspirone hydrochloride tablets not be used concomitantly with an MAOI.

Serotonin Syndrome The development of a potentially life-threatening serotonin syndrome has been reported with SNRIs SSRIs, and other serotonergic drugs, including buspirone, alone but particularly with concomitant use of other serotonergic drugs (including triptans), with drugs that impair metabolism of serotonin (in particular, MAOIs, including reversible MAOIs such as linezolid and intravenous methylene blue), or with antipsychotics or other dopamine antagonists. Serotonin syndrome symptoms may include mental status changes (e.g., agitation, hallucinations, delirium, and coma), autonomic instability (e.g., tachycardia, labile blood ressure, dizziness, diaphoresis, flushing, hyperthermia), neuromuscular changes (e.g., tremor, rigidity, myoclonus, hyperreflexia, incoordination), seizures, and/or gastrointestinal symptoms (e.g., nausea, vomiting, diarrhea).

Patients should be monitored for emergence of serotonin syndrome. The concomitant use of buspirone with MAOIs intended to treat depression is contraindicated. Buspirone should also not be started in a patient who is being treated with reversible MAOIs such as linezolid or intravenous methylene blue.

All reports with methylene blue that provided information on the route of administration involved intravenous administration in the dose range of 1 mg/kg to 8 mg/kg. There have been no reports involving the administration of methylene blue by other routes (such as oral tablets or local tissue injection) or at lower doses. There may be circumstances when it is necessary to initiate treatment with a reversible MAOI such as linezolid or intravenous methylene blue in a patient taking buspirone.

Buspirone should be discontinued before initiating treatment with the reversible MAOI [see CONTRAINDICATIONS , DOSAGE AND ADMINISTRATION AND DRUG INTERACTIONS ]. If concomitant use of buspirone with a 5-hydroxytryptmine receptor agonist (triptan) is clinically warranted, careful observation of the patient is advised, particularly during treatment initiation and dose increases. The concomitant use of buspirone with serotonin precursors (such as tryptophan) is not recommended.

Treatment with buspirone and any concomitant serotonergic or antidopaminergic agents, including antipsychotics, should be discontinued immediately if the above events occur and supportive symptomatic treatment should be initiated. Because buspirone hydrochloride tablets have no established antipsychotic activity, it should not be employed in lieu of appropriate antipsychotic treatment.

ADVERSE REACTIONS (See also PRECAUTIONS) Commonly Observed The more commonly observed untoward events associated with the use of buspirone hydrochloride tablets not seen at an equivalent incidence among placebo-treated patients include dizziness, nausea, headache, nervousness, lightheadedness, and excitement. Associated with Discontinuation of Treatment One guide to the relative clinical importance of adverse events associated with buspirone hydrochloride tablets is provided by the frequency with which they caused drug discontinuation during clinical testing.

Approximately 10% of the 2200 anxious patients who participated in the buspirone hydrochloride tablets premarketing clinical efficacy trials in anxiety disorders lasting 3 to 4 weeks discontinued treatment due to an adverse event. The more common events causing discontinuation included: central nervous system disturbances (3.4%), primarily dizziness, insomnia, nervousness, drowsiness, and lightheaded feeling; gastrointestinal disturbances (1.2%), primarily nausea; and miscellaneous disturbances (1.1%), primarily headache and fatigue.

In addition, 3.4% of patients had multiple complaints, none of which could be characterized as primary. Incidence in Controlled Clinical Trials The table that follows enumerates adverse events that occurred at a frequency of 1% or more among buspirone hydrochloride patients who participated in 4-week, controlled trials comparing buspirone hydrochloride tablets with placebo. The frequencies were obtained from pooled data for 17 trials.

The prescriber should be aware that these figures cannot be used to predict the incidence of side effects in the course of usual medical practice where patient characteristics and other factors differ from those which prevailed in the clinical trials. Similarly, the cited frequencies cannot be compared with figures obtained from other clinical investigations involving different treatments, uses, and investigators. Comparison of the cited figures, however, does provide the prescribing physician with some basis for estimating the relative contribution of drug and nondrug factors to the side-effect incidence rate in the population studied.

TREATMENT-EMERGENT ADVERSE EXPERIENCE INCIDENCE IN PLACEBO-CONTROLLED CLINICAL TRIALS *(Percent of Patients Reporting) Buspirone Placebo Adverse Experience (n=477) (n=464) Cardiovascular Tachycardia/Palpitations 1 1 CNS Dizziness 12 3 Drowsiness 10 9 Nervousness 5 1 Insomnia 3 3 Lightheadedness 3 - Decreased Concentration 2 2 Excitement 2 - Anger/Hostility 2 - Confusion 2 - Depression 2 2 EENT Blurred Vision 2 - Gastrointestinal Nausea 8 5 Dry Mouth 3 4 Abdominal/Gastric Distress 2 2 Diarrhea 2 - Constipation 1 2 Vomiting 1 2 Musculoskeletal Musculoskeletal Aches/Pains 1 - Neurological Numbness 2 - Paresthesia 1 - Incoordination 1 - Tremor 1 - Skin Skin Rash 1 - Miscellaneous Headache 6 3 Fatigue 4 4 Weakness 5 - Sweating/Clamminess 1 - * Events reported by at least 1% of buspirone hydrochloride patients are included. — Incidence less than 1%.

Other Events Observed During the Entire Premarketing Evaluation of Buspirone Hydrochloride Tablets During its premarketing assessment, buspirone hydrochloride tablets were evaluated in over 3500 subjects. This section reports event frequencies for adverse events occurring in approximately 3000 subjects from this group who took multiple doses of buspirone hydrochloride tablets in the dose range for which buspirone is being recommended (i.e., the modal daily dose of buspirone hydrochloride tablets fell between 10 mg and 30 mg for 70% of the patients studied) and for whom safety data were systematically collected.

The conditions and duration of exposure to buspirone hydrochloride tablets varied greatly, involving well-controlled studies as well as experience in open and uncontrolled clinical settings. As part of the total experience gained in clinical studies, various adverse events were reported. In the absence of appropriate controls in some… [Excerpted — this section continues on DailyMed.]

PRECAUTIONS General Interference with Cognitive and Motor Performance Studies indicate that buspirone hydrochloride tablets are less sedating than other anxiolytics and that it does not produce significant functional impairment. However, its CNS effects in any individual patient may not be predictable. Therefore, patients should be cautioned about operating an automobile or using complex machinery until they are reasonably certain that buspirone treatment does not affect them adversely.

While formal studies of the interaction of buspirone hydrochloride with alcohol indicate that buspirone does not increase alcohol-induced impairment in motor and mental performance, it is prudent to avoid concomitant use of alcohol and buspirone. Potential for Withdrawal Reactions in Sedative/Hypnotic/Anxiolytic Drug- Dependent Patients Because buspirone hydrochloride tablets do not exhibit cross-tolerance with benzodiazepines and other common sedative/hypnotic drugs, it will not block the withdrawal syndrome often seen with cessation of therapy with these drugs.

Therefore, before starting therapy with buspirone hydrochloride tablets, it is advisable to withdraw patients gradually, especially patients who have been using a CNS-depressant drug chronically, from their prior treatment. Rebound or withdrawal symptoms may occur over varying time periods, depending in part on the type of drug, and its effective halflife of elimination. The syndrome of withdrawal from sedative/hypnotic/anxiolytic drugs can appear as any combination of irritability, anxiety, agitation, insomnia, tremor, abdominal cramps, muscle cramps, vomiting, sweating, flu-like symptoms without fever, and occasionally, even as seizures.

Possible Concerns Related to Buspirone's Binding to Dopamine Receptors Because buspirone can bind to central dopamine receptors, a question has been raised about its potential to cause acute and chronic changes in dopamine-mediated neurological function (e.g., dystonia, pseudo-parkinsonism, akathisia, and tardive dyskinesia). Clinical experience in controlled trials has failed to identify any significant neuroleptic-like activity; however, a syndrome of restlessness, appearing shortly after initiation of treatment, has been reported in some small fraction of buspirone-treated patients.

The syndrome may be explained in several ways. For example, buspirone may increase central noradrenergic activity; alternatively, the effect may be attributable to dopaminergic effects (i.e., represent akathisia). See ADVERSE REACTIONS : Postmarketing Experience.

Information for Patients To assure safe and effective use of buspirone hydrochloride tablets, the following information and instructions should be given to patients: Do not take a monoamine oxidase inhibitor (MAOI). Ask your healthcare provider or pharmacist if you are not sure if you take an MAOI, including the antibiotic linezolid. Do not take an MAOI within 2 weeks of stopping buspirone unless directed to do so by your physician Do not start buspirone if you stopped taking an MAOI in the last 2 weeks unless directed to do so by your physician.

Inform your physician about any medications, prescription or non-prescription, alcohol, or drugs that you are now taking or plan to take during your treatment with buspirone hydrochloride tablets. Inform your physician if you are pregnant, or if you are planning to become pregnant, or if you become pregnant while you are taking buspirone hydrochloride tablets. Inform your physician if you are breast-feeding an infant.

Until you experience how this medication affects you, do not drive a car or operate potentially dangerous machinery. You should take buspirone hydrochloride tablets consistently, either always with or always without food. During your treatment with buspirone hydrochloride tablets, avoid drinking large amounts of grapefruit juice.

Laboratory Tests There are no specific laboratory tests recommended. Drug Interactions Psychotropic Agents MAO inhibitors: The… [Excerpted — this section continues on DailyMed.]

DRUG ABUSE AND DEPENDENCE Controlled Substance Class Buspirone hydrochloride is not a controlled substance. Physical and Psychological Dependence In human and animal studies, buspirone has shown no potential for abuse or diversion and there is no evidence that it causes tolerance, or either physical or psychological dependence. Human volunteers with a history of recreational drug or alcohol usage were studied in two double-blind clinical investigations.

None of the subjects were able to distinguish between buspirone hydrochloride tablets and placebo. By contrast, subjects showed a statistically significant preference for methaqualone and diazepam. Studies in monkeys, mice, and rats have indicated that buspirone lacks potential for abuse.

Following chronic administration in the rat, abrupt withdrawal of buspirone did not result in the loss of body weight commonly observed with substances that cause physical dependency. Although there is no direct evidence that buspirone hydrochloride tablets causes physical dependence or drug-seeking behavior, it is difficult to predict from experiments the extent to which a CNS-active drug will be misused, diverted, and/or abused once marketed. Consequently, physicians should carefully evaluate patients for a history of drug abuse and follow such patients closely, observing them for signs of buspirone hydrochloride tablets misuse or abuse (e.g., development of tolerance, incrementation of dose, drug-seeking behavior).