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THC + CBD oromucosal spray

Cannabis extract

Brand names: Sativex (nabiximols)

Cannabis-based extracts are unlicensed or specially licensed preparations sometimes used under specialist supervision for certain refractory conditions such as treatment-resistant epilepsy or spasticity.

Dosing — being independently re-sourced

ClinCalc Pro is rebuilding its dose data from primary open sources — the manufacturer SmPC (eMC), the WHO Model Formulary and other official references — under clinician review. This drug's structured dose is not yet published here. Confirm all doses against the product SmPC and your local formulary before prescribing.

Clinical monograph

How it works

Effects derive chiefly from cannabinoids such as cannabidiol and tetrahydrocannabinol acting on the endocannabinoid system and other neuronal pathways, with the contribution of each constituent varying by preparation.

Prescribing in practice

  • Prescribing of unlicensed cannabis-based products should be initiated only by specialists on the General Medical Council specialist register, in line with national guidance.
  • Tetrahydrocannabinol-containing preparations can cause psychoactive effects, sedation and impaired cognition, and have abuse potential.
  • Product composition and quality vary between preparations, so equivalence between products cannot be assumed.

Monitoring

Monitor clinical response, psychiatric and cognitive effects, and tolerability, with review against the specific preparation's specialist recommendations.

Counselling the patient

  • These products should be taken only as directed by the specialist team.
  • Avoid driving or operating machinery if experiencing drowsiness or impaired concentration.
  • Report mood changes, hallucinations or excessive sedation.

Evidence & guidelines

Evidence remains limited for most indications; NICE advises specialist-led prescribing and notes that robust trial data are restricted to particular cannabinoid products.

Reference: NICE NG144; ABN MS spasticity; SmPC; Confirm identity and dosing against the manufacturer SPC (eMC) and NICE. Verify against your local formulary and current prescribing references before prescribing. Monograph status: clinician-reviewed (2026-07-04).

Related

Curated clinical cross-links plus same-class fallbacks.

Pathways