Medications That Can Cause Tactile Hallucinations
Anti-Parkinsonian medications, certain antipsychotics, and opioids are the most common medications that cause tactile hallucinations, which manifest as sensations of crawling, stinging, or biting on the skin without actual stimuli. 1
Common Medication Classes Associated with Tactile Hallucinations
Anti-Parkinsonian Medications
- Trihexyphenidyl can induce tactile hallucinations, particularly in elderly patients with Parkinson's disease 2
- Dopamine agonists used for Parkinson's disease are strongly associated with triggering tactile hallucinations, especially when doses are increased 3
- These hallucinations often occur in a clear sensorium and can persist for prolonged periods 3
Antipsychotics
- Loxapine and other first-generation antipsychotics may cause tactile hallucinations as part of their side effect profile 4
- Chlorpromazine, used for nausea management, can induce hallucinations at doses of 12.5-25 mg 3-4 times daily 5
- Haloperidol, while used to treat delirium with hallucinations, can paradoxically cause hallucinations in some patients 5
Serotonergic Medications
- Lorcaserin (Belviq), a serotonin receptor agonist used for weight management, can cause hallucinations by binding to 5-HT receptors 5
- At the recommended dose of 10 mg twice daily, lorcaserin selectively binds to 5-HT 2C receptors rather than 5-HT 2A and 5-HT 2B receptors, which are associated with hallucinations 5
Opioids
- Hydromorphone has been documented to cause both visual and tactile hallucinations, with immediate cessation of symptoms upon discontinuation 6
- Opioid-induced tactile hallucinations are rare compared to visual and auditory hallucinations but may be underreported 6
- Opioid rotation (switching to different opioids like fentanyl or methadone) may help manage opioid-associated hallucinations 7
Other Medications
- Benzodiazepines, particularly when used for delirium management, may paradoxically cause delirium with associated hallucinations 5
- Corticosteroids are implicated as risk factors for delirium with potential hallucinations 5
- Anticholinergic medications can contribute to perceptual disturbances including tactile hallucinations 5
Clinical Presentation and Assessment
- Tactile hallucinations typically manifest as formication (sensations of crawling, stinging, or biting on the skin) without evidence of actual infestation 1
- Patients may present with multiple types of hallucinations simultaneously (visual, auditory, and tactile) 1
- Existing psychiatric comorbidities may increase susceptibility to medication-induced tactile hallucinations 1
- Delirium assessment should be performed using standardized tools like CAM-ICU or ICDSC when medication-induced hallucinations are suspected 5, 7
Management Approach
- Identify and discontinue the offending medication when possible 2, 6
- For patients requiring continued treatment with the causative medication, consider dose reduction or switching to an alternative with lower risk 3
- In cases of antipsychotic-induced hallucinations, consider switching from first-generation to atypical antipsychotics like quetiapine, which has a lower risk of extrapyramidal side effects 5, 4
- For opioid-induced hallucinations, opioid rotation may be effective with 80-90% response rates 7
- Avoid combining multiple medications that can cause hallucinations, as this increases risk without clear additional benefit 7
Monitoring and Follow-up
- Monitor for resolution of hallucinations after medication discontinuation or adjustment 2, 6
- Assess for other medication side effects that may accompany hallucinations, such as extrapyramidal symptoms with antipsychotics 5
- Consider underlying conditions that may predispose to medication-induced hallucinations, particularly in elderly patients 5
Drug-induced tactile hallucinations should be considered in the differential diagnosis for patients presenting with unexplained tactile sensations, especially when temporal correlation with medication initiation or dose increase is present.