• Crack cocaine stimulates the central nervous system, causing negative effects to the body.Geostock/Photodisc/Getty Images
  
  More than 8 million Americans older than 12 have used crack cocaine at least once in their lifetimes, according to the 2008 National Survey on Drug Use and Health. This highly potent drug has caused many people to be addicted. Crack cocaine causes a wide array of health problems, and this illegal drug can lead to death, according to the Office of National Drug Control Policy.
  
  

Addiction

• Crack cocaine causes the body to make excess dopamine, according to the Center for Substance Abuse Research (CESAR), and dopamine causes a euphoric feeling. This feeling when using crack helps explain why people crave the drug after the effects wear off. It's not hard for users to become hooked, or addicted, to the chemical. The more crack a person uses, the more tolerant of the chemical he becomes, according to CESAR. Addicted users need more crack to achieve the desired euphoric feeling.
  
  

Heart Damage

• Crack cocaine causes the body's blood vessels to constrict, according to the Office of National Drug Control Policy, which can lead to cardiovascular problems. Abusing crack can cause blood pressure to increase, and the drug can also lead to an increased heart rate. Crack cocaine can also lead to a fatal heart attack.
  
  

Nasal Damage

• Many users prefer to snort crack cocaine because the high lasts a lengthy 15 to 30 minutes, compared to smoking crack, which only causes a five- to 10-minute high, according to the Office of National Drug Control Policy. Snorting crack may lead to a long-lasting high, it also causes a decreased sense of smell, swallowing problems and a continuous runny nose. Nosebleeds and hoarseness are also side effects of snorting crack cocaine.