What is the recommended approach for tapering off cannabis and Tetrahydrocannabinol (THC) to discontinue use?

Cannabis and THC Tapering Recommendations for Discontinuation

The recommended approach for tapering off cannabis and THC involves a gradual reduction over at least 7 days, with the rate guided by the patient's tolerance to dose reduction, rather than abrupt cessation which may trigger withdrawal symptoms.

Assessment Before Tapering

• Quantify current cannabis consumption patterns, including amount used per day, frequency of use, and method of consumption 1
• Document the type of cannabis product being used (smoked cannabis, CBD oil, THC oil) and its CBD/THC content if known 1
• Screen for cannabis use disorder (CUD) in patients consuming cannabis more than once per day using validated tools such as the revised Cannabis Use Disorder Identification Test 1
• Consider involving addiction medicine or psychiatry specialists for patients with very high cannabis consumption (more than twice the significant consumption thresholds) 1

Significant Cannabis Consumption Thresholds

• Greater than 1.5 g/day of smoked cannabis 1
• Greater than 300 mg/day CBD oil 1
• Greater than 20 mg/day THC oil 1
• Consumption of cannabis products with unknown CBD/THC content more than 2-3 times per day 1

Tapering Protocol

• Do not attempt cannabis weaning or cessation within 24 hours of planned discontinuation as this may increase risk of cannabis withdrawal syndrome (CWS) 1
• Begin tapering at least 7 days before planned discontinuation for optimal outcomes 1
• Set an initial target of reducing consumption to just below the significant consumption thresholds (e.g., if consuming 2 g/day of inhaled cannabis, aim first for 1.5 g/day) 1
• Follow a "start low, go slow" principle when adjusting doses to minimize adverse effects 2
• Allow sufficient time between dose reductions to properly assess effects, particularly with oral THC which may take 30 minutes to 2 hours to take effect 2
• For patients consuming cannabis products of unknown CBD/THC content, consider switching to products with known content to better manage the tapering process 1

Managing Withdrawal Symptoms

• Cannabis withdrawal symptoms typically begin 24-48 hours after cessation, peak between days 2-6, and can last up to 3 weeks in heavy users 3, 4
• Common withdrawal symptoms include anxiety, irritability, anger, disturbed sleep, depressed mood, and loss of appetite 3, 4
• Less common physical symptoms include chills, headaches, physical tension, sweating, and stomach pain 3, 4
• Supportive counseling and psychoeducation are first-line approaches for managing withdrawal 3
• For symptom management, consider:
  • Gabapentin for general withdrawal symptom management 5, 3
  • Nabilone, nabiximols, or dronabinol (synthetic cannabinoids) may be beneficial for severe withdrawal symptoms, but require expert guidance 1, 6
  • Avoid aggressive weaning of CBD products without expert guidance, as CBD may mask some adverse effects of THC 1

Special Considerations

• Do not wean CBD while maintaining THC consumption, as this could exacerbate adverse effects of THC 1
• Be aware that cannabis withdrawal can be more complicated in patients with concurrent mental health disorders and polysubstance use 3
• Monitor for cannabinoid hyperemesis syndrome, characterized by cyclic vomiting that may be relieved by hot showers/baths 6
• Be aware that withdrawal symptoms may precipitate relapse to cannabis use 3, 7

Monitoring During Tapering

• Regularly assess for withdrawal symptoms, particularly during days 2-6 after significant dose reductions 3, 4
• For patients using CBD products >300 mg/day, monitor liver enzymes due to risk of reversible liver enzyme abnormalities 2, 5
• Watch for common side effects including dizziness, confusion, dry mouth, and fatigue 5

Pitfalls to Avoid

• Avoid abrupt cessation in heavy users, which significantly increases withdrawal risk 1, 3
• Do not underestimate the clinical significance of cannabis withdrawal, which can be comparable to tobacco withdrawal in severity 8
• Be aware that simultaneous cessation of cannabis and tobacco (in co-users) produces more severe withdrawal symptoms than either substance alone 8
• Avoid "stacking doses" (taking additional doses before the first has taken effect) during the tapering process 2