Most painkillers classify as one of three types: narcotic analgesics, non-narcotic analgesics and nonsteroidal anti-inflammatory drugs. Doctors may prescribe other types of medicine to fight pain that are drugs primarily used for other conditions. Common painkillers include narcotics such as oxycodone, hydrocodone and morphine; the non-narcotic analgesic acetaminophen; and the NSAIDs aspirin, ibuprofen and naproxen sodium. Physicians must prescribe narcotics, but the other drugs have both over-the-counter and prescription-strength forms available. Only acetaminophen comes without common side effects of any sort.
Drowsiness
Taking different forms of painkillers may cause drowsiness as a common side effect. For some drugs, such as narcotics like oxycodone, or NSAIDs such as naproxen sodium, drowsiness does not pose a threat to the person's health and classifies as nonserious and temporary, usually occurring only during the first few days of use. Abnormal tiredness, when associated with the OTC drug ibuprofen, for example, does classify as serious and needs medical attention, the Mayo Clinic states.
Constipation
Often when a person starts using a new medicine, the drug can cause a disturbance in the bowels that induces constipation. Oxycodone, for example, can cause such a problem temporarily, but the cramps should end soon and defecation can take place. With the NSAID ibuprofen, constipation or its opposite, diarrhea, both mean serious medical problems may exist and require an immediate consultation with a physician. With the NSAID naproxen sodium, both diarrhea and constipation may occur, but they classify as nonserious side effects that usually clear without aid from a doctor, Drugs.com reports.
Nausea and Vomiting
Nausea and vomiting may occur with most types of painkillers, but for most of these drugs, the uncomfortable queasiness and throwing up occur as nonserious and temporary side effects. Such medications as hydrocodone, a narcotic, and NSAIDs such as naproxen sodium and aspirin, all may induce nausea and vomiting during the first few days of use, but then the problems go away on their own, MedlinePlus indicates. With ibuprofen, however, such side effects need medical help, the Mayo Clinic reports.
Pain
All forms of painkillers, with the exception of acetaminophen, have the potential to cause pain in various ways as common side effects. Most often, pain will feel minor and go away by itself. In some cases, the pain indicates something more serious. The most common form of nonserious pain induced by painkillers is headaches with narcotics and naproxen. Ibuprofen, however, may induce pain in the abdomen as well as in the throat, stomach and chest, the Mayo Clinic reports. Naproxen may induce pain in the chest and stomach. These kinds of side effects require medical attention.
