Marijuana
Overview: Marijuana is a psychoactive drug originating from the cannabis plant. The main psychoactive component and the active ingredient that produces intoxicating effects is delta-9-tetrahydrocannabinol (THC). THC is usually consumed by smoking a hand rolled marijuana cigarette, commonly known as a reefer or joint. The amount of THC ingested is dependent on the THC concentration in the marijuana, also known as the quality, how deeply the smoke is inhaled into the lungs, and how long it is held in the lungs before exhaling. The effects of THC are felt within seconds with peak levels being reached within 30 minutes and declining after an hour. Behavioral and psychological effects can last from 2-4 hours. However, low levels of THC remain in the body for several days and possibly several weeks after chronic marijuana use. These levels can be detected on urine drug tests. Urine drug tests can also be positive as a result of inhaling marijuana smoke, even if an individual did not smoke the joint. The urine test simply detects if marijuana exposure has occurred.
Acute effects of marijuana are the result of specific THC receptors in the brain being stimulated by the THC content in the marijuana. These receptors are located in areas of the brain that are important for short-term memory and motor control; however they do not affect the portion of the brain that controls breathing. Therefore, an individual is not in danger of death by decreased oxygen. The acute physiological effects of marijuana can increase the heart rate, and may alter an individual’s blood pressure. The size of the blood vessels in the eye will increase, resulting in bloodshot eyes. Individuals may also experience a dry mouth and an urge to drink fluids. Other effects are inconsistent and may be a result of expectations and THC concentrations, for example individuals may get very hungry, have the “munchies,” or have an altered sexual response. A feeling of euphoria, well-being, and peacefulness are generally expressed as the marijuana high, time may pass more slowly and events can appear to be lengthened.
The long term effects of smoking marijuana are usually a result of chronic marijuana use. Individuals may feel as though they get high faster, however the individual’s technique has probably improved and they are getting more THC into their system with fewer joints. Nevertheless, the body does develop tolerance to marijuana. Conversely, with moderate use there is no physical dependence and mild psychological dependence.
Smoking marijuana can affect the lungs resulting in asthma or other breathing difficulties. It has been found that smoking 1-3 joints daily produces about the same lung damage and potential cancer risk as smoking 5-15 tobacco cigarettes daily.
Marijuana can effect the reproductive systems of both men and women. Marijuana decreases the level of testosterone in males, reducing sperm count in semen, and increasing the percentage of abnormally formed sperm. In females, marijuana can reduce the level of luteinizing hormone (LH), the hormone that is necessary for the fertilized egg to implant in the uterus. Little or no effect on fertility has been observed even with these changes.
What Thielen Student Health Center Can Do For You: Prevention, Education, and Outreach (PEO) in the Wellness Center can provide prevention programs regarding marijuana to campus organizations, residence halls, fraternities, and sororities. For more information about these programs contact the Office of Prevention, Education, and Outreach at 515-294-1868.
Last update: 09 Dec 2008
For more information, please contact:
Iowa State University
Thielen Student Health Center
515-294-5801
