Because of potential use as therapeutic agents, additional toxicologic studies on pure cannabinoids and cannabis extracts were conducted. Monkeys received a single iv dose of cannabidiol (CBD) or cannabichromene (CBCH) as an aqueous emulsion and LD50s were 212 and 270 mg/kg, respectively. The larger doses of CBD elicited tremors, convulsions, hypopnea, bradycardia, and cardiac failure. Survivors from smaller doses recovered in 1–3 days and liver weights increased 19–142%. CBCH evoked a dose-related hyperpnea and salivation initially but subsequent CNS inhibition resulted in apnea and bradycardia. Liver weights were elevated 8–71% and kidney weights 10–155% and pulmonary irritation, nephritis, increased BUN, and decreased serum electrolytes, hemoglobin, and RBC were found. Hashish oil containing 11.6 or 31.1% Δ9-THC caused muscle spasms, salivation, dyspnea, arrhythmia, and hypothermia and the LD50s were 326 and 435 mg/kg, respectively. Survivors recovered in a few days; lung and spleen congestion were common. Five day iv treatment with hashish oil 65–260 mg/kg) initiated similar toxicity and tolerance developed by Day 4. Growth rates were inhibited 7–20% and liver, kidney, and heart weights increased 20–100%. Delayed lethality occurred in two monkeys; histopathology included injection site necrosis, hemorrhagic foci in lungs, heart, intestines, and endocrines. Ninetyday oral treatment with CBD (30–300 mg/kg) had little effect but liver and kidney weights rose 13–56% above controls without morphologic changes. Decreased testicular size and inhibition of spermatogenesis occurred. The temporal pattern of adverse responses differentiated CBD, CBCH, and hashish oil.