Morphine

Morphine is highly addictive. Tolerance (the need for higher and higher doses to maintain the same effect) and physical and psychological addiction to Morphine develop quickly. Withdrawal from Morphine causes nausea, tearing, yawning, chills, and sweating lasting up to three days. Morphine crosses the placental barrier, and babies born to Morphine-using mothers go through Morphine withdrawal.

Addictive drugs, such as Morphine activate the brain's reward systems. The promise of reward is very intense, causing the individual to crave Morphine and to focus his or her activities around the taking of Morphine. The ability of Morphine to strongly activate brain reward mechanisms and its ability to chemically alter the normal functioning of these systems can produce a Morphine addiction. Morphine also reduces a person's level of consciousness, harming the ability to think or be fully aware of present surroundings.