Signs and Symptoms of Use

Several regularly observed physical effects of marijuana include:

• Substantial increase in heart rate 
• Bloodshot eyes
• Dry mouth and throat
• Increased appetite
• Chronic sore throat

Use of marijuana also has mental effects that may include:

• Impaired or reduced short-term memory and comprehension
• Altered sense of time
• Changed sensory perception–sight, smell, hearing, touch
• Reduced ability to perform tasks requiring concentration and coordination, such as driving a car

Research also shows that people do not retain knowledge when they are “high”. Motivation and cognition may be altered, making the acquisition of new information difficult. Marijuana also can produce paranoia and psychosis.