What It Does:
Nicotine is as addictive as heroin or cocaine, which makes it extremely difficult to quit. Those who start smoking or vaping before age 21 have the hardest time breaking the habit.
Physical effects of nicotine use include rapid heartbeat, increased blood pressure, shortness of breath, and a greater likelihood of colds and flu.
Users have an increased risk for lung diseases, heart disease, and stroke. Brain development can be affected, even in older teens.
Withdrawal symptoms of nicotine include anxiety, anger, restlessness, and insomnia.