Continued high doses can cause heart problems, infections, malnutrition, death. Damage to lungs, reproductive and brain functions. Slows reflexes, increases forgetfulness, throws off space and distance judgment. Increased risk of birth defects to user's children. Overdose can cause psychosis, convulsions, coma, death.
Frequent use can cause permanent loss of mental function.
Tolerance, physical and psychological dependence. Overdose can cause coma, convulsions, respiratory arrest, death. Possible malnutrition, infection,hepatitis. Use of dirty needles is a leading cause of spread disease. Reduced reaction time, confusion.