Other Stimulants Stimulants can cause increased heart and respiratory rates, elevated blood pressure, dilated pupils, and decreased appetite. In addition, users may experience sweating, headache, blurred vision, dizziness, sleeplessness, and anxiety. Extremely high doses can cause a rapid or irregular heartbeat, tremors, loss of coordination, and even physical collapse. An amphetamine injection creates a sudden increase in blood pressure that can result in stroke, very high fever, or heart failure. In addition to the physical effects, users report feeling restless, anxious, and moody.
Higher doses intensify the effects.
Persons who use large amounts of amphetamines over a long period of time can develop an amphetamine psychosis that includes hallucinations, delusions, and paranoia. All forms of cannabis have negative physical and mental effects. 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. Motivation and cognition may be altered, making the acquisition of new information difficult. Marijuana can also produce paranoia and psychosis.