Marijuana finds its application in the field of medicines and many patients of cancer and AIDS find quick relief owing to the drug. Diseases like arthritis, multiple sclerosis, epilepsy, and depression can also be treated with the help of this drug. Reports often reveal that marijuana has not only been able to improve the effects of prescriptions drugs but also eradicates the negative impact of drugs sued for the treatment of cancer and AIDS. This was proved when the Compassionate Use Act of 1996 in California legalized the medical use of the drug. For several years the drug has been used for medical purposes. For instance, in 1941, the drug has been used in the US Pharmacopoeia. Several challenges have been faced from the side of the law with respect to the prohibition of the medical use of the drug encouraged government investigations and all these procedures have ensured the worthiness as well as the safety of the application of this drug in medicines. The chief administrative law judge of the Drug Enforcement Administration, Francis L Young, on September 6, 1988, declared after the required hearings: “Marijuana, in its natural form, is one of the safest therapeutically active substances known. The evidence in this record clearly shows that marijuana has been accepted as capable of relieving the distress of great numbers of very ill people and doing so with safety under medical supervision. It would be unreasonable, arbitrary, and capricious for DEA to continue to stand between those sufferers and the benefits of this substance in light of the evidence in this record.” The above declaration may prove to be the ideal evidence for the utility of marijuana in medical science. A study carried out at the John Hopkins University of Baltimore deals with the impact of the drug on cognitive status.