Synergy Health and Wellness Clinic · Patient Education
Understanding THC: Dosing, Effects and Safety
Educational information about oral THC, inhaled THC, and prescription dronabinol. Dose categories are illustrative and are not validated therapeutic thresholds.
Oral THC: starting doses and dose categories
For patients new to cannabis, initiate at the lowest feasible dose, generally 1 mg oral THC or less for particularly sensitive patients, and titrate gradually. Existing users require assessment of their current dose, frequency, route, tolerance, therapeutic response, and adverse effects; prior use does not guarantee tolerance to a new product or route.
| Dronabinol indication | Labeled oral-capsule dosing | Illustrative dose at BSA 1.9 m² |
|---|---|---|
| AIDS-associated anorexia | 2.5 mg twice daily initially; maximum 10 mg twice daily | Fixed mg dose; BSA conversion does not apply |
| Chemotherapy-induced nausea/vomiting after inadequate conventional antiemetics | 5 mg/m² per dose initially; 4–6 doses/day; may reduce to 2.5 mg/m²; maximum 15 mg/m² per dose | Initial: 9.5 mg per dose; reduced: 4.75 mg per dose; maximum: 28.5 mg per dose |
The 1.9 m² value is an illustrative body-surface area, not a universal adult average. Actual BSA must be calculated for each patient. The CINV regimen is administered 1–3 hours before chemotherapy and every 2–4 hours afterward, per labeling; consult current product labeling.
| Oral THC category | Amount per dose | Clinical interpretation |
|---|---|---|
| Low | 1–5 mg | New users should generally begin at the bottom of this range, not automatically at 5 mg. |
| Intermediate | 10–20 mg | May produce substantial intoxication, particularly without tolerance. |
| High | 30–40 mg or more | Higher risk of anxiety, paranoia, nausea, dizziness, tachycardia, confusion and impairment; not a starting target. |
Inhaled THC: smoking versus dry-herb vaporization
Under Utah law, smoking or combusting medical cannabis is prohibited; vaporization of approved medical cannabis products is permitted. Smoking cannabis flower results in THC losses through combustion and sidestream smoke. For illustration, an inhalation of 20% THC flower may contain approximately 3–5 mg THC, while an inhalation from a 90% THC vape cartridge may contain approximately 5–6 mg THC. These are approximate product- and device-dependent exposure estimates, not measured amounts absorbed into the bloodstream. Dry-herb vaporization at 350–375°F (177–191°C) generally releases THC more gradually, while 400–430°F (204–221°C) may release THC faster per inhalation but may also increase thermal degradation products. Device design, airflow, inhalation technique, and session duration affect exposure. Effects from inhaled THC generally begin within seconds to minutes and typically last approximately 1–3 hours, although residual impairment can persist longer.
Oral THC: delayed effects and avoiding premature redosing
Oral THC may produce delayed, prolonged intoxication, in part because the active metabolite 11-hydroxy-THC contributes to psychoactive effects. The clinical effects can persist substantially longer than patients expect from inhalation. Patients should avoid additional oral doses while waiting for the first dose to reach its full effect. Effects may not peak for several hours and can last 6–8 hours or longer.
Edible effects are delayed and prolonged; avoid rapid repeat dosing. Avoid driving while impaired. Individualize for age, comorbidities, interactions and prior adverse reactions.