The body's tolerance to pain is increased. In large doses, heroin can reduce or eliminate respiration causing death. Overdose is a major risk of heroin injestion since users are not aware of the amount and purity of the drug. Heroin is also harmful to a developing fetus. Pregnant women who are dependent on heroin have a higher risk for spontaneous abortions, breech deliveries, premature births and stillbirths.
Babies born to heroin-addicted mothers often have withdrawal symptoms similar to adults.
These symptoms may last serveral weeks or months. Long-term Effects One of the most adverse affects of heroin use is addiction. Heroin is highly addictictive because it activates many regions of the brain, especially the pleasure-producing areas. Physical dependence develops with higher doses of the drug. With physical dependence, the body adapts to the presence of the drug and withdrawal symptoms appear when the drug usage stops.