CBD Oil Was Safe and Well-Tolerated for Long COVID Symptoms in Small Trial | Research

The takeaway

A 21-week open-label feasibility trial of CBD-dominant cannabis oil in 12 people with long COVID found the treatment was safe with no serious adverse events and high participant adherence, though efficacy could not be assessed without a control group.

Long COVID researchers, cannabinoid medicine clinicians, and long COVID patients

100% treatment adherence over 21 weeks with no serious adverse events

What the researchers found

All 12 participants adhered to the treatment protocol for the full 21 weeks with no serious adverse events. Response rates for research assessments exceeded 90%. The study demonstrated feasibility of CBD treatment in long COVID, but the open-label design without a control group means efficacy conclusions cannot be drawn.

Why it matters

Long COVID affects millions and has limited treatment options. This study establishes that CBD-dominant cannabis oil is feasible and safe to study in this population, paving the way for larger controlled trials. The high adherence rate is notable for a 21-week study.

The numbers in context

12 participants (1 male, 11 female). CBD dose: up to 150 mg/day. Treatment: 21 weeks. 0 serious adverse events. Over 90% completion rate for outcome measures. 100% treatment adherence.

How the study worked

Single-arm open-label feasibility trial. 12 adults with diagnosed long COVID received up to 3 mL/day of MediCabilis 5% CBD Oil (50 mg CBD/mL, <2 mg THC/mL) for 21 weeks, followed by 3 weeks without treatment. Monthly patient-reported outcomes and daily symptom self-reports were collected via smartphone app. Wearable technology tracked heart rate, activity, sleep, and oxygen saturation.

What this study cannot tell us

Very small sample (n=12). No control group means no efficacy conclusions possible. Open-label design introduces placebo effects and expectancy bias. 11 of 12 participants were female, limiting generalizability. Recruitment challenges were noted.

How to read the evidence

Very small open-label feasibility study; demonstrates safety and feasibility only, not efficacy.

When this study was published

2024 study

The bigger picture

CBD is being explored for multiple post-infectious syndromes due to its anti-inflammatory and immunomodulatory properties. Establishing safety and feasibility is the necessary first step before investing in larger efficacy trials.

Questions still open

Would a larger placebo-controlled trial show CBD benefit for long COVID? Which specific long COVID symptoms might be most responsive to CBD? What is the optimal dose and duration?

Common questions

Can CBD help with long COVID?

This small feasibility study showed CBD oil was safe and well-tolerated for long COVID patients over 21 weeks, but without a control group, it cannot tell us whether CBD actually improves symptoms. Larger controlled trials are needed.

Is CBD safe for long COVID patients?

In this 12-person trial, CBD-dominant oil (up to 150 mg/day) caused no serious adverse events over 21 weeks, with all participants completing the full protocol.

Read the original research

Feasibility of a cannabidiol-dominant cannabis-based medicinal product for the treatment of long COVID symptoms: A single-arm open-label feasibility trial.

British journal of clinical pharmacology, 90(4), 1081-1093

View on PubMed ↗Publisher’s paper ↗

Citation

Thurgur, Hannah; Lynskey, Michael; Schlag, Anne Katrin; Croser, Carol; Nutt, David John; Iveson, Elizabeth. (2024). Feasibility of a cannabidiol-dominant cannabis-based medicinal product for the treatment of long COVID symptoms: A single-arm open-label feasibility trial.. British journal of clinical pharmacology, 90(4), 1081-1093. https://doi.org/10.1111/bcp.15988