The pick: THC, not CBN
Pick THC for nausea. Two THC drugs carry FDA approval for chemotherapy-induced nausea and vomiting. CBN carries none. Human trial data for nausea exists for THC. Human trial data for CBN and nausea does not exist in published form.
medical cannabis for nausea dosage
CBN is a backup at best. Buy it after THC fails, not before.
THC: what the evidence shows
Dronabinol (Marinol) and nabilone (Cesamet) are synthetic THC. The FDA approved both for chemotherapy-induced nausea and vomiting. Dronabinol also holds approval for appetite loss in AIDS patients.
medical marijuana for chemo induced nausea
A 2001 BMJ meta-analysis pooled 30 randomized trials. Cannabinoids beat conventional antiemetics such as prochlorperazine in chemo patients. Sedation and dizziness rates ran higher.
The 2017 National Academies report found substantial evidence that oral cannabinoids prevent and treat chemotherapy-induced nausea and vomiting.
Doses used in trials
- Dronabinol: 5 mg per square meter of body surface, 1 to 3 hours before chemo, then every 2 to 4 hours. Maximum 4 to 6 doses per day.
- Nabilone: 1 mg to 2 mg, twice daily.
- Inhaled THC from dispensaries: 2 mg to 10 mg per dose. Onset 2 to 10 minutes.
CBN: what it actually has
CBN is a breakdown product. THC oxidizes into CBN over time through heat, light, and air exposure. Old flower tests high in CBN for that reason.
CBN binds CB1 and CB2 receptors with lower affinity than THC. Receptor binding is not a nausea trial. Most CBN evidence sits in animal models and lab dishes.
No published human trial has tested isolated CBN as a nausea treatment. Sleep claims for CBN are common. Nausea claims are not. The FDA has approved CBN for nothing.
Side by side
- Human nausea trials: THC yes, CBN no.
- FDA approval for nausea: THC yes, CBN no.
- Typical dose: THC 2.5 mg to 10 mg, CBN 5 mg to 25 mg in gummies.
- Onset: oral THC 30 to 60 minutes, inhaled THC 2 to 10 minutes, oral CBN 1 to 2 hours.
- Side effects: THC causes sedation, dizziness, dry mouth, fast heart rate, and anxiety at high doses. CBN human side effect data is thin.
- Legal status: dronabinol is Schedule III under federal law. Nabilone is Schedule II. CBN sold in stores sits in a gray zone with no FDA oversight.
Options, ranked
- Dronabinol (Marinol) generic. Prescription. FDA label for chemo nausea. Schedule III. Cheapest approved route with a generic version.
- Nabilone (Cesamet). Prescription. FDA label for chemo nausea. Schedule II. Stronger sedation reports than dronabinol.
- THC-dominant oral products. State-licensed dispensaries. Dose 2.5 mg to 10 mg. No FDA label, no batch guarantee.
- THC plus CBN blends. CBN at 5 mg to 25 mg. No nausea trial backs the CBN portion. Buy only if THC alone failed.
Bottom line
THC has numbers, labels, and trials. CBN has a pathway and a marketing story. For nausea, start with THC. Add CBN later if you want, and expect no proven nausea benefit from it.