Nonresponse to initial pharmacotherapy for obsessive compulsive disorder in adults and young people

Consider modifying treatment for obsessive compulsive disorder (OCD) in an adult or young person if symptoms persist despite:

  • using an effective dose of at least 2 selective serotonin reuptake inhibitors (SSRIs) or serotonin noradrenaline reuptake inhibitors (SNRIs) as sequential monotherapy, each for a minimum of 4 weeks (full benefit may take 8 weeks or longer); and
  • discounting alternative reasons for treatment nonresponse.

Options for treatment modification include:

  • combining psychosocial interventions (if not already used) with pharmacotherapy
  • a trial of clomipramine (see below)
  • referral to a psychiatrist or an age-appropriate mental health service—psychiatrists may use clomipramine or an augmenting agent (see below).

For treatment considerations for females of childbearing potential, including advice on contraception, preconception planning and psychotropic use, see here.

For considerations in managing anxiety disorders such as OCD during the perinatal period, see here or for considerations in partners, see here.

Clomipramine may be uniquely effective for some patients, but intolerance commonly limits its use and toxicity in overdose must be considered. Use lower doses in frail or older people. Clomipramine can cause changes in cardiac conduction—an electrocardiogram (ECG) should be obtained before treatment is started and repeated once the dose is stabilised, usually after 6 weeks. If either ECG shows abnormalities, seek advice from a cardiologist before starting or continuing treatment. If clomipramine is considered appropriate for OCD, use:

clomipramine 25 to 75 mg orally, at night, increasing as tolerated by 25 to 50 mg every 2 to 3 days to a target dose of 150 mg. If response is inadequate, further dose increases may be needed, to a maximum of 300 mg at night. If an acceptable response is achieved, continue treatment for 6 to 12 months, then consider deprescribing. obsessive compulsive disorder (adult) clomipramine clomipramine clomipramine

Psychiatrists may combine an antidepressant with low-dose aripiprazole or risperidone for treatment-resistant OCD. However, there is limited evidence supporting this practice and the adverse effects of antipsychotics should be considered.