Management of cannabis use
Long term high dose cannabis use may be complicated by comorbid mental health disorders and is associated with a withdrawal syndrome characterised by anxiety, insomnia and agitation.
1. Assessment
Management of cannabis use requires initial assessment including:
- Pattern, quantity and setting of use, including whether smoked in joints or bongs
- Comorbid other drug use, including tobacco
- Previous episodes of cessation or reduction and symptoms
- Physical and mental health history
- Mental state examination
- Urine drug screen may be helpful in documenting other drug use (although may be difficult to interpret for cannabis due to variable elimination of cannabinoids).
2. Management of cannabis dependence
2.1 Withdrawal management
Medical management of cannabis withdrawal is usually straight forward; however specialist support may be required in patients with severe comorbid psychiatric disorders or high risk polysubstance use.
Cannabis withdrawal symptoms commence 24 – 48 hours after last use and peak from days 4 – 7. Cravings and sleep disturbance, as well as symptoms such as irritability, may persist for months in some patients.
Patients requesting treatment of cannabis use usually have a history of chronic use and treatment should be carefully planned including provision of a supportive home setting. Medical care should be focussed on symptom management, and can include treatment of insomnia and anxiety with small doses of sedative agents (benzodiazepines / major tranquilisers), sedating antidepressants such as mirtazapine, as well as antiemetics. Note that benzodiazepine / hypnotic use should be restricted to short-term use only.
These medications may carry risk of toxicity and they should be closely monitored. It is advised that doses are dispensed on a limited pick-up basis (such as weekly). Patients should be advised about sleep hygiene and encouraged to maintain hydration.
Management of nicotine withdrawal may be required in some patients and smoking cessation advice should be provided.
2.2 Post withdrawal care
Key components of managing cannabis use problems include strategies to reduce relapse risk and management of comorbid mental health problems such as depression and anxiety.
Further information for patients is available locally (contact DirectLine on 1800 888 236) or check websites such as information from the better health channel on the Victoria Drug Service directory.
On-line counselling is available at Counselling Online.
Disclaimer
This information is a general guide for the management of cannabis withdrawal. Consultation with a specialist service (e.g. DACAS) is recommended for advice about patients using multiple drugs or with serious medical or psychiatric conditions. The drug doses given are a guide only and should be adjusted to suit individuals.