CBD (cannabidiol)

Cannabidiol (CBD) is a non-intoxicating cannabinoid that does not produce the psychoactive effects associated with THC. Unlike THC it has minimal direct CB1 binding; its mechanisms of action involve multiple non-cannabinoid-receptor pathways including 5-HT1A serotonin receptors, TRPV1 channels, and modulation of endocannabinoid breakdown enzymes (FAAH inhibition).

CBD has the strongest controlled-trial evidence base of any cannabinoid for specific refractory paediatric epilepsies — Dravet syndrome, Lennox-Gastaut syndrome, and tuberous-sclerosis-related seizures, where pharmaceutical-grade formulations have established place in therapy. Emerging evidence supports use in anxiety disorders at controlled doses, sleep disturbance as adjunct, and some inflammatory and pain conditions, though the evidence quality varies substantially by indication.

Clinically relevant CBD interacts with several CYP450 substrates — most notably clobazam (CYP2C19), valproate (multiple pathways with hepatotoxicity risk), warfarin (CYP2C9), and tacrolimus (CYP3A4) — and regular monitoring (LFTs, INR, drug levels) is required in these combinations.

In South Africa, two distinct regulatory tracks exist: **low-dose CBD** (≤600 mg per pack, ≤20 mg per recommended dose) is Schedule 0 / over-the-counter under Gazette 43347 (2020) for general-health claims only — no disease-specific therapeutic claims permitted. **Clinically relevant doses** for epilepsy, refractory anxiety, or seizure-spectrum indications are pharmaceutical-grade products accessed via Section 21 under specialist oversight.