After cataracts, glaucoma is the second leading cause of blindness. Increased intraocular pressure is characteristic of this disorder and is related to its destructive effects on the retina. Cannabis has been shown convincingly to reduce intraocular pressure about 25%. This effect is noted only with inhaled or ingested cannabis, and not when applied topically.
Because of its very short duration of action, cannabis cannot be recommended as primary treatment for glaucoma, however many patients have reported that when used in conjunction with prescription medications, cannabis reduces intraocular pressure significantly more than with prescription medication alone. Clearly, this is an area that needs further study.
Multiple sclerosis (MS) and Rheumatoid arthritis (RA)
MS is a progressive autoimmune (the person’s own body mistakenly attacks itself) neurological disorder caused by a loss of the lining (myelin) of nerve cells or neurons in the central nervous system. This results in the loss of conductivity of nerve impulses and ultimately loss of function. Symptoms include muscle pain and spasticity, loss of balance, anxiety and depression, urinary incontinence, blindness, and involuntary muscle movements.
Patients report that cannabis reduces pain and spasticity, improves their outlook and sense of well being while enhancing their ability to deal with their disease. Patients reported improvement has not been correlated objectively in clinical trials, however patients reported subjective improvement has been very consistent.
Several patients have reported a reduction in the progression of their disease while others have even a reversal in their level of impairment. These reports must be considered anecdotal for now but cannabinoid effects on the CB-2 receptors in the lymphoid tissue could offer a possible mechanism of action. Further study is clearly indicated.