A synthetic opioid commonly known for treating addicts, it also is an effective pain reliever that doctors are prescribing more.

Methadone, a drug long valued for treating heroin addiction and for soothing chronic pain, is increasingly being abused by recreational drug users and is causing an alarming increase in overdoses and deaths

2. Oxycodone (Oxycontin, Roxicodone, Tylox, Percocet)

Painkiller that often is combined in pills with aspirin or acetaminophen or with a time-release mechanism that offers a longer-term pain relief.

Oxycodone has a high abuse potential and is prescribed for moderate to high pain relief associated with injuries, bursitis, dislocation, fractures, neuralgia, arthritis, and lower back and cancer pain. It is also used postoperatively and for pain relief after childbirth. OxyContin, Percocet, Percodan, and Tylox are trade name oxycodone products.
 

Central nervous system depressant that is most commonly used to treat insomnia and anxiety.

The drug Xanax is a longer duration Benzodiazepine which is prescribed to treat insomnia in patients with daytime anxiety or patients with Generalized Anxiety Disorder (GAD) and Panic Disorders.
 

Painkiller named after Morpheus, the Greek God of dreams.

Morphine is highly addictive. Tolerance (the need for higher and higher doses to maintain the same effect) and physical and psychological dependence develop quickly. Withdrawal from morphine causes nausea, tearing, yawning, chills, and sweating lasting up to three days.

5. Hydrocodone (Vicodin, Lortab, Lorcet)

A semi synthetic opiate painkiller and cough suppressant. It is the most frequently prescribed opiate painkiller in the United States.

Anxiety, constipation, decreased mental & physical performance, difficulty breathing, difficulty urination, dizziness, drowsiness, dry throat, emotional dependence, exaggerated feeling of depression, extreme calm (sedation), exaggerated sense of well-being, fear, itching, mental clouding, mood changes, nausea & vomiting, rash, restlessness, sluggishness and  tightness in chest are all possible side effects.

6. Fentanyl (Actiq, Fentonara, Duragestic)

Powerful pain reliever that comes in many forms, including lollipops, tablets and patches.

Fentanyl can produce drug dependence similar to that produced by morphine. Fentanyl has the potential for abuse, often leading to physical and psychological dependence, but may be a necessary evil to control chronic pain.

7. Propoxyphene (Darvon)

An opioid analgesic used for mild to moderate pain and as a cough suppressant.

When abused is taken orally, chewed, crushed (then snorted like cocaine), or crushed (then dissolved in water and injected like heroin).

8. Carisoprodol (Soma)

Muscle relaxant drug used in pain relief. It's not considered a controlled substance in most states.

Individuals of all ages abuse Soma. Data reported in the National Survey on Drug Use and Health indicate that 2,276,000 U.S. residents aged 12 and older used Soma nonmedically at least once in their lifetime.

Most often used to treat anxiety. Inspired the Rolling Stones song Mother's Little Helper.

Valium depresses the nervous system much like alcohol and is abused by all segments of society. Valium is both physically and psychologically addicting and as is considered one of the toughest addictions to break.

Potent opioid painkiller that is a derivative of morphine.

Hydromorphone's abuse potential comes from the fact that its euphoric intravenous rush is very similar to heroin's. Hydromorphone is one of the most prescribed opioids in the relief of pain for the terminally ill due to its minimal side effects and high potency.