TREATMENT Naltrexone
The psychiatrist discusses pharmacologic options to treat kleptomania with Ms. B and her mother. After considering the risks, benefits, adverse effects, and alternative treatments (including the option of no pharmacologic treatment), the mother consents and Ms. B assents to treatment with naltrexone, 25 mg/d. Before starting this medication, both the mother and Ms. B receive detailed psychoeducation describing naltrexone’s interactions with opioids. They are told that if Ms. B has a traumatic injury, they should inform the treatment team that she is taking naltrexone, which can acutely precipitate opiate withdrawal.
Before initiating pharmacotherapy, a comprehensive metabolic profile is obtained, and all values are within the normal range. After 1 week, naltrexone is increased to 50 mg/d. The medication is well tolerated, without any adverse effects.
The author’s observations
Behavioral interventions, such as covert sensitization and systemic desensitization, often are used to treat kleptomania.8 There are no FDA-approved medications for this condition. Opioid antagonists have been considered for the treatment of kleptomania.7
Mu-opioid receptors exist in highest concentrations in presynaptic neurons in the periaqueductal gray region and spinal cord and have high affinity for enkephalins and beta-endorphins. They also are involved in the reward and pleasure pathway. This neurocircuit is implicated in behavioral addiction.9
Naltrexone is an antagonist at μ-opioid receptors. It blocks the binding of endogenous and exogenous opioids at the receptors, particularly at the ventral tegmental area. By blocking the μ-receptor, naltrexone inhibits the processing of the reward and pleasure pathway involved in kleptomania. Naltrexone binds to these receptors, preventing the euphoric effects of behavioral addictions.10 This medication works best in conjunction with behavioral interventions.8
Naltrexone is a Schedule II drug. Use of naltrexone to treat kleptomania or other impulse control disorders is an off-label use of the medication. Naltrexone should not be prescribed to patients who are receiving opiates because it can cause acute opiate withdrawal.
Liver function tests should be monitored in all patients taking naltrexone. If liver function levels begin to rise, naltrexone should be discontinued. Naltrexone should be used with caution in patients with preexisting liver disease.11
OUTCOME Marked improvement
Ms. B’s K-SAS scores are evaluated 2 weeks after starting naltrexone. The results show a marked reduction in the urge to steal and in stealing behavior, and Ms. B’s mother reports no incidents of stealing in the previous week.
Ms. B is maintained on naltrexone, 50 mg/d, for 2 months. On repeated K-SAS scores, her mother rates Ms. B’s symptoms “very much improved” with “occasional” stealing. Ms. B is discharged from the intensive outpatient program.