Starting Treatment
Phase 4 of care for patients with DI involves initiating therapy, which includes demonstrating empathy by reflecting on the detrimental effects of the patient’s reported sensations on their quality of life. “Emphasize that you are not questioning their experience, and that you don’t doubt that they feel things on their skin,” Dr. Murase said. “Recommend medications on an empirical or ‘trial and error’ pragmatic basis. I often tell patients, ‘I will never give up on you if you will never give up on me.’”
For treating patients with DI, her first-generation antipsychotic of choice is pimozide. She starts at a dose of 0.5 mg, building up to 2-3 mg once a day. Haloperidol is another option: 0.5 mg to start, building up to 1-5 mg every night at bedtime. “This requires monitoring for bone suppression via CBC and hypermetabolic complications via fasting lipids and HbA1c,” she said. “There is also an increased risk of prolonged QT with pimozide and risk of extrapyramidal symptoms and tardive dyskinesia.”
Second-generation antipsychotics to consider include risperidone (0.5 mg to start, building up to 102 mg at bedtime); olanzapine (2.5 mg to start, building up to 5-10 mg at bedtime); aripiprazole (2-5 mg to start, building up to 10-15 mg a day), and quetiapine (12.5 mg to start, building up to 200 mg at bedtime).
For all medical therapy she recommends starting patients with a low dose, increasing by 0.5 mg every 2-3 weeks, and let them be “stable and comfortable” for 3-4 months, and then taper down the dose by 0.5 mg every 2-4 weeks or more slowly. In the medical chart, Dr. Murase recommends avoiding use of the terms “psychosis” and “delusions.” Instead, “formication” (tactile hallucination of insects crawling on or within the skin) or “cutaneous dysesthesia” are better terms if patients access their records, she said.
Dr. Murase reported having no relevant disclosures.