Maybe cigarettes aren't the only things that should have warning labels on them. MSN Health and Fitness published an article about the deadliest drugs in the United States. Interesingly enough, this list refers to only legal medications in the United States, or those that the Federal Drug Administration has approved for public use. The "deadliest" drug list refers to drugs that are known to be responsible for deaths, but does not indicate whether the deaths are related to prescription use, over-the-counter use, or abuse of the medications.

The list is from the article, but the information relating to each drug is from my own research, primarily from www.drugs.com.

The list ranks the number of drug deaths from  1998-2005.
1    Oxycodone :This is known as a painkiller medication and is particularly known because it is often abused as a painkiller. According to the article, it is responsible for 5,548 known deaths in the years listed above.

2    Fentanyl  is also a pain medication, but according to Drugs.com should be used for "breakthrough cancer pain" and not for headaches or back pain, despite the similar classification to oxycodone.                      

During the time period listed above, 3,545 deaths were linked to Fentanyl.

3    Clozapine  is an antipsychotic often prescribed for bipolar disorder and other anxiety disorders. It is often used in conjunction with other medications and may commonly be abused.     3277 deaths were reported to be linked to this medication.

4    Morphine    is a Prescription opioid painkiller* that is familar to most of us as a drug that is also abused out of the hospital. 1616 deaths were associated with morphine in the above-mentioned time period.

5    Acetaminophen is the active ingredient in Tylenol, which seems pretty harmless but " The most serious side effect is liver damage due to large doses, chronic use or concomitant use with alcohol or other drugs that also damage the liver. Chronic alcohol use may also increase the risk of stomach bleeding."  1393 deaths were reported to be related to the use and/or abuse of this medication.

6    Methadone  is used primarily as a substitute for those who are addicted to Heroin and is reported to be safe when used under close supervision. Some of the deaths associated with this may be due to abuse of the drug.   1258 deaths were reported with the use of this drug during the time period.

7    Infliximab   is  used to treat autoimmune diseases such as Crohn's Disease. It is classified as an "Immune-system modulating drug" and is possibly responsible for 1228 deaths during the above years.

8    Interferon beta  is also classified as an "immune-system modulating drug" but is used for treating Multiple Sclerosis (MS). 1178 deaths were attributed to this drug.

9    Risperidone or Risperdal is an antipsychotic used in the treatment of bipolar disorder and schizophrenia. Most of the deaths associated with this drug are associated with its past use in treatment of dementia. 1093 people died while using this drug.

10    Etanercept    is indicated for treating rheumatoid arthritis.  It is an immune-system modulating drug that was reportedly linked to 1034 deaths.