Marijuana, or "pot," is a mixture of dried, shredded leaves, stems, seeds and flowers of the hemp plant Cannabis sativa, according to Drugs.com. It is usually smoked, but some users cook it into foods. The main active chemical in marijuana is called THC, which is delta-9-tetrahydrocannabinol.

Electrolytes, such as sodium, calcium and potassium, are important minerals in the body responsible for maintaining acid levels, fluid balance, and muscle functioning. A number of factors can lead to electrolyte imbalance, such as excessive sweating, medical conditions, and medications.

The American Academy of Dermatology says that an itch consists of a complex process that involves nerves responding to the release of histamine and sending signals to the brain. Implications of itchy skin range from insect bites to drug sensitivity.

Test anxiety is a type of performance anxiety. People who suffer from test anxiety often have other types of anxiety, in particular social anxiety. Nonpharmacological methods are considered the first line of treatment, but if they fail, or if the anxiety is truly incapacitating, medications can be helpful.

Prescription drugs have their place in our medically advanced society. There are many diseases people would die from if not for prescription drugs, and some prescription drugs seem to make life easier when you have a small ailment such as the flu or a cough. But prescription drugs have a dark side as well.

Cocaine is an addictive illegal drug that causes tolerance, withdrawal, preoccupation with the drug, unsuccessful attempts to stop use, severe cravings, and continued use despite severe consequences. It can also cause sudden death.

Methadone is a synthetic narcotic used to relieve moderate to serious pain or as an aid to heroin withdrawal. Also known as Diskets, Dolophine and Methadose, this controlled substance requires a prescription and comes in liquid, tablet and injectable forms.

According to The National Institute on Drug Abuse, six million Americans 12 years old and older tried cocaine in 2006 and 1.5 million had used crack cocaine at least once in the past year. One of the most addictive drugs, cocaine gives users a euphoric feeling and makes them more energetic.

Infections of the microscopic Giardia parasites, also known as Giardia duodenalis or Giardia lamblia, usually clear up in two to six weeks on their own. However, repeated infections or infections in people with compromised immune systems can have long-term effects, some of them severe.

Xanax is the trade name for alprazolam, a benzodiazepine drug usually prescribed for anxiety disorders, panic disorders and mild depression. As with other psychoactive drugs, Xanax may cause dependence, and you can experience withdrawal when you stop using it.

According to the Higher Education Center for Alcohol and Other Drug Prevention, nearly one-third of all Americans have tried marijuana at some point in their lives. Marijuana, also called pot or weed, is considered a gateway drug that leads to harder drugs with more serious consequences.

Infants who have been exposed to smoked cocaine, or crack, during pregnancy typically show a wide spectrum of symptoms after birth, although it is not uncommon for some infants to be asymptomatic, says the National Institute on Drug Abuse. At first, many infants appear irritable.