- Includes marijuana, hashish, hashish oil, and tetrahydrocannabinol (THC).
- Regularly observed physical effects of cannabis are a substantial increase in heart rate, bloodshot eyes, a dry mouth and throat, and increased appetite. Use of cannabis may impair or reduce short-term memory and comprehension, alter sense of time, and reduce ability to perform tasks requiring concentration and coordination, such as driving a car. Research also shows that students do not retain knowledge when they are “high.” Motivation and cognition may be altered, making the acquisition of new information difficult. Marijuana can also produce paranoia and psychosis. Because users often inhale the unfiltered smoke deeply and then hold it in their lungs as long as possible, marijuana damages the lungs and pulmonary system. Marijuana smoke contains more cancer-causing agents than tobacco. Long-term users of cannabis may develop psychological dependence and require more of the drug to get the same effect.