Propoxyphene N 100 W APAP 650 tabs control pain, but as of November 2010, manufacturers of drugs containing propoxyphene have withdrawn them from use in the United States, according to MedicineNet. Companies marketed the drug, a combination of propoxyphene and acetaminophen, as Darvocet-N, Darvocet A500 and Wygesic. The U.S. Food and Drug Administration determined that propoxyphene presents serious potential heart risks that outweigh its pain-reducing ability, explains Consumer Reports. APAP is an abbreviation for acetaminophen, according to Drugs.com.
Even when patients take propoxyphene as their doctors recommend, the drug is linked to abnormal heart rhythms that can be deadly, and people have reported thousands of problems, reports Consumer Reports. Propoxyphene relieves pain but does not eliminate its presence, explains MedicineNet. Scientists do not know exactly how the narcotic works, but it may stimulate the brain's opioid receptors. The drug is not as strong as codeine, morphine and hydrocodone, which are also narcotics. Propoxyphene suppresses coughs, works as a sedative and depresses respiratory activity.
Acetaminophen is a fever-reducing analgesic that is not narcotic, notes MedicineNet. The drug relieves pain by raising a patient's pain tolerance level. Acetaminophen combined with propoxyphene produces greater pain relief than either drug can produce alone. In October 1972, the U.S. FDA approved the combination drug for pain relief use, but as of 2015, drug companies no longer market it in the United States.