In 1974, the first of several studies appeared examining issues of pain relief with Cannabis (Noyes and Baram, 1974).
This article examined five case studies of patients who volitionally experimented with the substance to treat
painful conditions. Three had chronic headaches, and found relief by smoking Cannabis that was comparable, or superior
to ergotamine tartrate and aspirin.

One subsequent study of Cannabis pertained to pain tolerance in an experimental protocol (Milstein et al., 1975). A
statistically significant increase in pain threshold wasobserved after smoking Cannabis in both naive (8%
increase) and experienced subjects (16% increase).

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