Quetiapine for K2 (Synthetic Cannabinoid) Withdrawal
There is no established evidence-based dose of quetiapine (Seroquel) specifically for K2 withdrawal, as no guidelines or studies directly address this indication. However, based on quetiapine's use for acute agitation and psychosis in similar clinical contexts, a reasonable approach would be to start with 25-50 mg orally as needed for agitation or psychotic symptoms, with reassessment after 1-2 hours 1.
Recommended Dosing Strategy
For acute agitation or psychosis during K2 withdrawal:
- Initial dose: 25-50 mg orally (immediate release formulation) 1
- Reassess after 30-60 minutes to determine if additional dosing is needed 1
- Maximum initial titration: Up to 100-200 mg in the first 24 hours if symptoms persist, divided into 2-3 doses 2, 3
- Use the lowest effective dose for the shortest duration necessary 1
Clinical Context and Rationale
K2 withdrawal typically presents with anxiety, agitation, psychosis, and autonomic instability. While quetiapine is used off-label for managing agitation and psychosis in various substance withdrawal states, the evidence base comes from delirium management and acute psychosis treatment rather than synthetic cannabinoid withdrawal specifically 1.
Key dosing considerations:
- Start low in young, antipsychotic-naïve patients (25 mg) to assess tolerance 1, 3
- Quetiapine causes sedation, which may be beneficial for agitation but requires monitoring for oversedation 1, 4
- Titration schedule for ongoing treatment (if needed beyond acute management): Day 1: 50 mg, Day 2: 100 mg, Day 3: 200 mg, Day 4: 300 mg 3
Important Safety Considerations
Monitor for these specific risks:
- Orthostatic hypotension and dizziness are common, especially in young patients who may be volume depleted 1, 4
- Excessive sedation can occur, particularly if combined with benzodiazepines (which should be avoided unless treating concurrent alcohol/benzodiazepine withdrawal) 1
- Metabolic effects are less concerning with short-term use but should be considered if treatment extends beyond a few days 1
Critical Pitfalls to Avoid
Do not use quetiapine as first-line monotherapy for K2 withdrawal. Address the underlying withdrawal syndrome with supportive care, hydration, and symptom-specific management first 1.
Avoid combining with benzodiazepines unless specifically treating concurrent sedative-hypnotic withdrawal, as this combination increases risk of oversedation and respiratory depression 1.
Do not continue beyond the acute withdrawal period (typically 3-7 days for synthetic cannabinoids) without reassessing the need for ongoing antipsychotic treatment 1, 3.
Alternative Considerations
If quetiapine is ineffective or poorly tolerated:
- Haloperidol 2.5-5 mg IM/IV may be used for severe agitation, though it carries higher risk of extrapyramidal symptoms 1
- Olanzapine 2.5-5 mg orally or IM is an alternative atypical antipsychotic with similar efficacy 1
- Supportive care alone may be sufficient for mild-to-moderate symptoms without psychosis 1
The lack of specific evidence for quetiapine in K2 withdrawal means treatment should be guided by symptom severity rather than a fixed protocol, with frequent reassessment and dose adjustment based on clinical response 1, 3.