This section is from the book "Materia Medica And Therapeutics: An Introduction to the National Treatment of Disease", by John Mitchell Bruce. Also available from Amazon: The pharmacology and therapeutics of the materia medica.
Positive knowledge on these points is wanting; but the drug certainly does not derange the stomach and intestines like opium. It is never used externally. Internally the extract forms a useful corrective of some griping purgatives, such as podophyllin or colocynth.
The action of cannabis indica is ill understood. It chiefly affects the convolutions, producing a species of intoxication; disordered consciousness of personality, locality, and time; and exaltation of the feelings, with pleasing grandiose ideas and hallucinations. Noisy, restless delirium, with muscular excitement, or, more commonly, sleep supervenes; and therewith any pain that may be present is relieved. The heart and blood pressure appear to be first stimulated and afterwards depressed.
Cannabis indica was formerly used as a hypnotic and anodyne, when opium disagreed or had been taken in excess; but, from its uncertainty, it has been generally replaced by chloral. Combined with bromide of potassium, it is useful in mania. More frequently it is given as a special anodyne and antispasmodic in dysmenorrhoea, monorrhagia and hysteria. It may also be tried in neuralgia, and in spasmodic asthma (as cigarettes), when other remedies fail.
Nothing is definitely known respecting the excretion of cannabis indica. It increases the amount of urine, probably through the blood pressure.