Pronunciation

(me proe BA mate)

Index Terms

• Equanil

Dosage Forms

Excipient information presented when available (limited, particularly for generics); consult specific product labeling.

Tablet, Oral:

Generic: 200 mg, 400 mg

Pharmacologic Category

• Antianxiety Agent, Miscellaneous

Pharmacology

Affects the thalamus and limbic system; also appears to inhibit multineuronal spinal reflexes

Metabolism

Hepatic

Excretion

Urine (8% to 20% as unchanged drug); feces (10% as metabolites)

Onset of Action

Sedation: ~1 hour

Half-Life Elimination

10 hours

Use: Labeled Indications

Anxiety: Management of anxiety disorders

Limitations of use: Meprobamate is not a preferred treatment option for anxiety disorders per the American Psychiatric Association, World Federation of Societies of Biological Psychiatry, and British Association for Psychopharmacology guidelines (APA [Stein 2009]; BAP [Baldwin 2014]; WFSBP [Bandelow 2012]).

Contraindications

Hypersensitivity to meprobamate, related compounds (including carisoprodol), or any component of the formulation; acute intermittent porphyria

Dosing: Adult

Anxiety: Oral: 1,200 to 1,600 mg/day in 3 to 4 divided doses; maximum: 2,400 mg/day

Discontinuation: In patients with excessive dosage continued for weeks or months, meprobamate should be tapered off gradually over 1 to 2 weeks to avoid withdrawal symptoms such as anxiety, anorexia, or insomnia.

Dosing: Pediatric

Anxiety: Oral:

Children ≥6 years: 200 to 600 mg/day in 2 to 3 divided doses

Discontinuation: In patients with excessive dosage continued for weeks or months, meprobamate should be tapered off gradually over 1 to 2 weeks to avoid withdrawal symptoms such as anxiety, anorexia, or insomnia.

Adolescents: Refer to adult dosing.

Dosing: Renal Impairment

There are no dosage adjustments provided in manufacturer’s labeling; however, the following adjustments have been recommended (Aronoff 2007): Adults:

CrCl 10 to 50 mL/minute: Administer every 9 to 12 hours

CrCl <10 mL/minute: Administer every 12 to 18 hours

Hemodialysis: No dosage adjustment necessary

Peritoneal dialysis: Administer every 12 to 18 hours

Continuous renal replacement therapy (CRRT): Administer every 9 to 12 hours

Dosing: Hepatic Impairment

There are no dosage adjustments provided in manufacturer’s labeling; use with caution.

Drug Interactions

Alcohol (Ethyl): CNS Depressants may enhance the CNS depressant effect of Alcohol (Ethyl). Monitor therapy

Analgesics (Opioid): CNS Depressants may enhance the CNS depressant effect of Analgesics (Opioid). Management: Avoid concomitant use of opioid analgesics and benzodiazepines or other CNS depressants when possible. These agents should only be combined if alternative treatment options are inadequate. If combined, limit the dosages and duration of each drug. Consider therapy modification

Azelastine (Nasal): CNS Depressants may enhance the CNS depressant effect of Azelastine (Nasal). Avoid combination

Blonanserin: CNS Depressants may enhance the CNS depressant effect of Blonanserin. Consider therapy modification

Brimonidine (Topical): May enhance the CNS depressant effect of CNS Depressants. Monitor therapy

Buprenorphine: CNS Depressants may enhance the CNS depressant effect of Buprenorphine. Management: Consider reduced doses of other CNS depressants, and avoiding such drugs in patients at high risk of buprenorphine overuse/self-injection. Initiate buprenorphine patches (Butrans brand) at 5 mcg/hr in adults when used with other CNS depressants. Consider therapy modification

Cannabis: May enhance the CNS depressant effect of CNS Depressants. Monitor therapy

Chlormethiazole: May enhance the CNS depressant effect of CNS Depressants. Management: Monitor closely for evidence of excessive CNS depression. The chlormethiazole labeling states that an appropriately reduced dose should be used if such a combination must be used. Consider therapy modification

Chlorphenesin Carbamate: May enhance the adverse/toxic effect of CNS Depressants. Monitor therapy

CNS Depressants: May enhance the adverse/toxic effect of other CNS Depressants. Monitor therapy

Dimethindene (Topical): May enhance the CNS depressant effect of CNS Depressants. Monitor therapy

Doxylamine: May enhance the CNS depressant effect of CNS Depressants. Management: The manufacturer of Diclegis (doxylamine/pyridoxine), intended for use in pregnancy, specifically states that use with other CNS depressants is not recommended. Monitor therapy

Dronabinol: May enhance the CNS depressant effect of CNS Depressants. Monitor therapy

Droperidol: May enhance the CNS depressant effect of CNS Depressants. Management: Consider dose reductions of droperidol or of other CNS agents (e.g., opioids, barbiturates) with concomitant use. Consider therapy modification

Flunitrazepam: CNS Depressants may enhance the CNS depressant effect of Flunitrazepam. Consider therapy modification

HYDROcodone: CNS Depressants may enhance the CNS depressant effect of HYDROcodone. Management: Avoid concomitant use of hydrocodone and benzodiazepines or other CNS depressants when possible. These agents should only be combined if alternative treatment options are inadequate. If combined, limit the dosages and duration of each drug. Consider therapy modification

HydrOXYzine: May enhance the CNS depressant effect of CNS Depressants. Monitor therapy

Kava Kava: May enhance the adverse/toxic effect of CNS Depressants. Monitor therapy

Lofexidine: May enhance the CNS depressant effect of CNS Depressants. Monitor therapy

Magnesium Sulfate: May enhance the CNS depressant effect of CNS Depressants. Monitor therapy

Methotrimeprazine: CNS Depressants may enhance the CNS depressant effect of Methotrimeprazine. Methotrimeprazine may enhance the CNS depressant effect of CNS Depressants. Management: Reduce adult dose of CNS depressant agents by 50% with initiation of concomitant methotrimeprazine therapy. Further CNS depressant dosage adjustments should be initiated only after clinically effective methotrimeprazine dose is established. Consider therapy modification

MetyroSINE: CNS Depressants may enhance the sedative effect of MetyroSINE. Monitor therapy

Minocycline: May enhance the CNS depressant effect of CNS Depressants. Monitor therapy

Mirtazapine: CNS Depressants may enhance the CNS depressant effect of Mirtazapine. Monitor therapy

Nabilone: May enhance the CNS depressant effect of CNS Depressants. Monitor therapy

Orphenadrine: CNS Depressants may enhance the CNS depressant effect of Orphenadrine. Avoid combination

Oxomemazine: May enhance the CNS depressant effect of CNS Depressants. Avoid combination

OxyCODONE: CNS Depressants may enhance the CNS depressant effect of OxyCODONE. Management: Avoid concomitant use of oxycodone and benzodiazepines or other CNS depressants when possible. These agents should only be combined if alternative treatment options are inadequate. If combined, limit the dosages and duration of each drug. Consider therapy modification

Paraldehyde: CNS Depressants may enhance the CNS depressant effect of Paraldehyde. Avoid combination

Perampanel: May enhance the CNS depressant effect of CNS Depressants. Management: Patients taking perampanel with any other drug that has CNS depressant activities should avoid complex and high-risk activities, particularly those such as driving that require alertness and coordination, until they have experience using the combination. Consider therapy modification

Piribedil: CNS Depressants may enhance the CNS depressant effect of Piribedil. Monitor therapy

Pramipexole: CNS Depressants may enhance the sedative effect of Pramipexole. Monitor therapy

ROPINIRole: CNS Depressants may enhance the sedative effect of ROPINIRole. Monitor therapy

Rotigotine: CNS Depressants may enhance the sedative effect of Rotigotine. Monitor therapy

Rufinamide: May enhance the adverse/toxic effect of CNS Depressants. Specifically, sleepiness and dizziness may be enhanced. Monitor therapy

Selective Serotonin Reuptake Inhibitors: CNS Depressants may enhance the adverse/toxic effect of Selective Serotonin Reuptake Inhibitors. Specifically, the risk of psychomotor impairment may be enhanced. Monitor therapy

Sodium Oxybate: May enhance the CNS depressant effect of CNS Depressants. Management: Consider alternatives to combined use. When combined use is needed, consider minimizing doses of one or more drugs. Use of sodium oxybate with alcohol or sedative hypnotics is contraindicated. Consider therapy modification

Suvorexant: CNS Depressants may enhance the CNS depressant effect of Suvorexant. Management: Dose reduction of suvorexant and/or any other CNS depressant may be necessary. Use of suvorexant with alcohol is not recommended, and the use of suvorexant with any other drug to treat insomnia is not recommended. Consider therapy modification

Tapentadol: May enhance the CNS depressant effect of CNS Depressants. Management: Avoid concomitant use of tapentadol and benzodiazepines or other CNS depressants when possible. These agents should only be combined if alternative treatment options are inadequate. If combined, limit the dosages and duration of each drug. Consider therapy modification

Tetrahydrocannabinol: May enhance the CNS depressant effect of CNS Depressants. Monitor therapy

Thalidomide: CNS Depressants may enhance the CNS depressant effect of Thalidomide. Avoid combination

Trimeprazine: May enhance the CNS depressant effect of CNS Depressants. Monitor therapy

Yohimbine: May diminish the therapeutic effect of Antianxiety Agents. Monitor therapy

Zolpidem: CNS Depressants may enhance the CNS depressant effect of Zolpidem. Management: Reduce the Intermezzo brand sublingual zolpidem adult dose to 1.75 mg for men who are also receiving other CNS depressants. No such dose change is recommended for women. Avoid use with other CNS depressants at bedtime; avoid use with alcohol. Consider therapy modification

Adverse Reactions

Frequency not defined.

Cardiovascular: Abnormal electroencephalogram, cardiac arrhythmia, peripheral edema, palpitations, severe hypotension, syncope, tachycardia

Central nervous system: Ataxia, chills, dizziness, drowsiness, euphoria, headache, overstimulation, paradoxical excitation, paresthesia, slurred speech, vertigo

Dermatologic: Dermatitis, erythema multiforme, skin rash, Stevens-Johnson syndrome

Endocrine & metabolic: Exacerbation of porphyria

Gastrointestinal: Diarrhea, nausea, proctitis, stomatitis, vomiting

Genitourinary: Anuria, oliguria

Hematologic & oncologic: Agranulocytosis, aplastic anemia, bruise, eosinophilia, immune thrombocytopenia, leukopenia, petechia, purpura

Hypersensitivity: Anaphylaxis, angioedema, hypersensitivity reaction

Neuromuscular & skeletal: Weakness

Ophthalmic: Accommodation disturbance

Respiratory: Bronchospasm

Miscellaneous: Fever

Warnings/Precautions

Concerns related to adverse effects:

• Allergic reactions: May occur in patients with history of dermatological condition (usually by fourth dose).

• CNS depression: May cause CNS depression, which may impair physical or mental abilities; patients must be cautioned about performing tasks which require mental alertness (eg, operating machinery or driving). Effects may be potentiated when used with other sedative drugs or ethanol.

Disease-related concerns:

• Depression: Use with caution in patients with depression or suicidal tendencies.

• Drug abuse: Use with caution in patients with a history of drug abuse or acute alcoholism; potential for drug dependency exists. Tolerance, psychological and physical dependence may occur with prolonged use.

• Hepatic impairment: Use with caution in patients with hepatic impairment.

• Renal impairment: Use with caution in patients with renal impairment.

• Seizure disorder: Use with caution in patients with a history of seizure disorder.

Concurrent drug therapy issues:

• Drug-drug interactions: Potentially significant interactions may exist, requiring dose or frequency adjustment, additional monitoring, and/or selection of alternative therapy. Consult drug interactions database for more detailed information.

Other warnings/precautions:

• Withdrawal: Abrupt discontinuation may precipitate withdrawal. In patients with excessive dosage continued for weeks or months, meprobamate should be tapered off gradually over 1 to 2 weeks to avoid withdrawal symptoms such as anxiety, anorexia, or insomnia.

Monitoring Parameters

Anxiety symptoms, mental status, abuse/overuse

Pregnancy Considerations

Meprobamate crosses the placenta and is found in cord blood in concentrations similar to those in the maternal plasma. Maternal use may be associated with congenital malformations; avoid use during pregnancy.

Patient Education

• Discuss specific use of drug and side effects with patient as it relates to treatment. (HCAHPS: During this hospital stay, were you given any medicine that you had not taken before? Before giving you any new medicine, how often did hospital staff tell you what the medicine was for? How often did hospital staff describe possible side effects in a way you could understand?)

• Patient may experience headache, nausea, vomiting, diarrhea, fatigue, or anxiety. Have patient report immediately to prescriber signs of infection, enlarged lymph nodes, swelling of arms or legs, bruising, bleeding, urinary retention, change in amount of urine passed, difficulty breathing, severe loss of strength and energy, suicidal ideation, seizures, dysarthria, tachycardia, arrhythmia, behavioral changes, burning or numbness feeling, change in balance, vision changes, severe dizziness, passing out, or signs of Stevens-Johnson syndrome/toxic epidermal necrolysis (red, swollen, blistered, or peeling skin [with or without fever]; red or irritated eyes; or sores in mouth, throat, nose, or eyes) (HCAHPS).

• Educate patient about signs of a significant reaction (eg, wheezing; chest tightness; fever; itching; bad cough; blue skin color; seizures; or swelling of face, lips, tongue, or throat). Note: This is not a comprehensive list of all side effects. Patient should consult prescriber for additional questions.

Intended Use and Disclaimer: Should not be printed and given to patients. This information is intended to serve as a concise initial reference for healthcare professionals to use when discussing medications with a patient. You must ultimately rely on your own discretion, experience and judgment in diagnosing, treating and advising patients.