Mental health functioning and severity of cannabis withdrawal among medical cannabis users with chronic pain.

Purpose: To describe patterns of cannabis withdrawal among a large sample of those who use medical cannabis and test the association between withdrawal symptomology and functioning.

Procedures: Adults ages 21 and older (N = 801) who were seeking medical cannabis certification (either for the first time or as a renewal) for chronic pain at medical cannabis clinics in southern Michigan completed baseline measures of cannabis use, withdrawal symptomology, functioning and other related constructs. Patients were included in the current study if they endorsed using cannabis at least weekly over the past three months. Of the persons in the baseline sample (N = 801), 83% endorsed using cannabis at this level of frequency and duration (N = 665).

Findings: Approximately two-thirds of the sample (67.8%) reported at least one moderate or severe withdrawal symptom. The most commonly observed symptom was sleep difficulties (50.3%), followed by anxiety (27.8%), irritability (26.7%), and appetite disturbance (25.2%). Patients with low mental functioning had significantly higher rates of withdrawal symptom endorsement than patients with high mental functioning. However, no association was observed between physical functioning and withdrawal symptom endorsement. These patterns of association were consistent in multivariate analyses that controlled for other potentially confounding variables.

Conclusions: Cannabis withdrawal symptomology is highly prevalent among patients who use medical cannabis at least three times a week. Helping patients recognize the association between poorer functioning and withdrawal may be an effective way to highlight potentially negative consequences of regular and moderate heavy use.