12,000 years ago civilizations cultured Cannabis sativa not for medicinal or recreational purposes but instead its properties were exploited to make ropes and fabric. Nobody must have imagined the vast possibilities of that plant then but we have come a long way now.Aryans are credited for using cannabis for recreational purposes before anyone else but that could just be due to lack of proper proof. Around 1000 BC, the Egyptians used cannabis to treat issues with the eyes and to treat inflammation. Interestingly, it was also used as an anesthetic when mixed with other liquids. It was highly regarded in respected written works of the time, including the Bible. And in the 1600s, the settlers brought the cannabis plant to North America. At the time, it was being used to treat depression and other mental health issues in England. It was considered widespread, mainstream medicine in the West to use cannabis to treat inflammation, headaches, insomnia, and menstrual cramps.But what makes cannabis so effective and one of the most famous source of plant derived drugs of the 21st century?The answer is Cannabinoids. Cannabinoids are the chemical compounds secreted by cannabis flowers that provide relief to an array of symptoms including pain, nausea, anxiety, and inflammation by acting on cannabinoid receptors in cells that alter neurotransmitter release in the brain. These work their medicinal magic by imitating compounds our bodies naturally produce, called endocannabinoids, which activate to maintain internal stability and health.EFFECTS OF CANNIBINOIDSAs evolution proceeded, the role that the cannabinoid system played in animal life continuously increased. It is now known that this system maintains homeostasis within and across the organizational scales of all animals. Within a cell, cannabinoids control basic metabolic processes such as glucose metabolism Cannabinoids regulate intercellular communication, especially in the immune and nervous systems. In general, cannabinoids modulate and coordinate tissues, organ and body systems (including the cardiovascular, digestive, endocrine, excretory, immune, musculo-skeletal, nervous, reproductive, and respiratory systems. The effects of cannabinoids on consciousness are not well understood, but are well known, and underlie recreational cannabis use. These effects also have therapeutic possibilities . Cannabinoids derived from plants are called phytocannabinoids. Other than phytocannabinoids and endocannabinoids even synthetic cannabinoids can act as a ligand for the cannabinoid receptors in the body.There are two kinds of cannabinoid receptors found in body; CB1 receptors which are primarily found in the brain and the CB2 receptors which are found in cells all over the body.Although Cannabis was criminalized by California in 1972, it was legalized for medical use in November,2016 and for recreational use on January 1,2018. How does this affect us? Alzheimer’s disease (AD), amyotrophic lateral sclerosis (ALS), cachexia/wasting syndrome, cancer, Crohn’s disease (CD), epilepsy and seizures, glaucoma, hepatitis C virus (HCV), human immunodeficiency virus (HIV)/acquired immunodeficiency syndrome (AIDS), multiple sclerosis (MS) and muscle spasticity, severe and chronic pain, severe nausea, and post-traumatic stress disorder (PTSD). These are the common disorders for which use of cannabis is recommended. CANNABINOIDS AND CANCERFor many years cannabis had been used by cancer patients expecting a relief from the deteriorating chemotherapies but now scientists have approved cannabis for medical use for them. In vivo and in vitro trials have indicated that cannabinoids inhibit tumor growth via several proposed mechanisms (e.g., suppression of cell proliferation, reduced cell migration, increased apoptosis) . While the studies so far have shown that cannabinoids can be safe in treating cancer, they do not show that they help control or cure the disease.CANNABINOIDS DRUGSCurrently there are two main drugs derived from cannabinoids;1. Dronabinol (Marinol®): Main component is THC (delta-9-tetrahydrocannabinol). Its recommended to treat nausea and vomiting caused by cancer chemotherapy as well as weight loss and poor appetite in patients with AIDS.2. Nabilone (Cesamet®): It is a synthetic cannabinoid that acts much like THC. It can be taken by mouth to treat nausea and vomiting caused by cancer chemotherapy when other drugs have not worked. Like many other drugs, even prescription cannabinoids, Dronabinol and Nabilone, can cause side effects and complications. Some people have trouble with increased heart rate, decreased blood pressure (especially when standing up), dizziness or lightheadedness, and fainting. These drugs can cause drowsiness as well as mood changes or a feeling of being “high” that some people find uncomfortable. They can also worsen depression, mania, or other mental illness. Some patients taking nabilone in studies reported hallucinations. The drugs may increase some effects of sedatives, sleeping pills, or alcohol, such as sleepiness and poor coordination. Patients have also reported problems with dry mouth and trouble with recent memory.CONCLUSION Although the positive effects of cannabinoids weigh more than the negatives, they shouldn’t be ignored. Medical decisions about pain and symptom management should be made between the patient and his or her doctor, balancing evidence of benefit and harm to the patient, the patient’s preferences and values, and any laws and regulations that may apply. Cannabinoids have come a long way from when they were discovered but we have more to discover and understand. Better scientific approaches and studies will help the world appreciate it and use it responsibly.