Cannabis and cannabinoids in dermatology: a systematic review and meta-analysis of quantitative outcomes

TL;DR

This study reviews and analyzes the effectiveness of cannabinoids in treating skin conditions, finding a modest reduction in itching but no significant benefits for other outcomes.

Contribution

The study provides a quantitative meta-analysis of cannabinoids' effects on dermatologic disorders, offering evidence-based insights into their clinical relevance.

Findings

Cannabinoids showed a statistically significant reduction in pruritus (SMD = −0.29).

No significant effects were observed for skin dryness, erythema, or quality of life.

Larger, standardized trials are needed to confirm therapeutic potential.

Abstract

Cannabinoids, present in Cannabis sativa, modulate the signaling and receptor expression of the endocannabinoid system (ECS), potentially impacting various skin conditions. However, current evaluations of their clinical effectiveness remain largely descriptive. This study aimed to quantitatively assess the effectiveness of cannabinoids, including Cannabis sativa extracts, in treating dermatologic disorders.

Systematic review and meta-analysis.

PubMed, Embase, Scopus, Web of Science, and CENTRAL from inception to 30 June 2024.

We included randomized controlled trials and observational studies that evaluated the efficacy or effectiveness of medical cannabis or cannabinoid-based interventions in managing dermatologic conditions, regardless of the comparator type.

Two reviewers independently extracted data and assessed risk of bias. Outcomes were categorized into subjective outcomes, objective outcomes, and disease-specific composite scores. Meta-analyses used standard mean differences (SMDs) with 95% confidence intervals (CIs). Study quality was assessed using RoB 2 and ROBINS-I tools.

We included 3,359 participants from eleven randomized controlled trials, three quasi-experimental studies, and three observational studies. Interventions included topical formulations of cannabis extract ointment, cannabidiol, N-acylethanolamine (PEA), alkylamides, and HU-210. A statistically significant reduction in pruritus was observed among participants treated with cannabinoids (SMD = −0.29, 95% CI: −0.52 to −0.06, I2 = 0%). No significant effects were found for skin dryness (SMD = −0.22, 95% CI: −0.58 to 0.14, I2 = 20%), erythema (SMD = −0.33, 95% CI: −0.65 to 0.00, I2 = 0%), or quality of life (SMD = −0.15, 95% CI: −0.64 to 0.34, I2 = 58%). Disease-specific scores for atopic dermatitis (SMD = −0.19, 95% CI: −0.44 to 0.05, I2 = 0%) and transepidermal water loss (SMD = 0.16, 95% CI: −0.60 to 0.93, I2 = 68%) also showed no significant differences.

Cannabinoids produced a modest but statistically significant reduction in pruritus, suggesting clinical relevance for symptom management. However, no significant benefits were observed for other dermatologic outcomes. Larger, standardized randomized trials are needed to clarify their therapeutic potential in dermatology.

identifier CRD42023397189.

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