|Pain Medications: How Long is Too Long?
There are many different types of pain medications available to the public. They can be obtained by prescription or over-the-counter. Consumers are constantly bombarded with advertisements selling all types of pain relievers for a variety of pain problems. Physicians are also encouraged by drug companies to prescribe or recommend medications.
Pain medications provide a valuable service to relieve suffering and enhance the quality of our lives. Unfortunately, they also often have significant side effects. Sometimes a pain medication causes more harm than good. When this occurs, the dose must be adjusted or the medicine should be discontinued. This article reviews several classes of popular pain medications to highlight those where long term use can cause problems.
Nonsteroidal antiinflammatory drugs (NSAIDs) are probably the most popular pain medications. They are easily obtained without a prescription. Some examples of NSAIDS are Motrin, Advil, and Aleve. Stronger dosages than those available over-the-counter can also be prescribed. NSAIDs are used to reduce pain, inflammation, and fever.
Their possible side effects include stomach upset, gastric ulcers, kidney disease, and increased risk of bleeding. They can increase peripheral edema (swelling of the arms and legs). They can interfere with treatment for hypertension and heart disease. Their possible adverse effects on cartilage and osteoarthritis have been raised. Some people have reported tinnitis (ringing in the ears) with long-term use. Usually NSAIDS can be stopped suddenly without complications but in some cases chronic users report a “rebound headache” when they suddenly stop. It is then necessary to gradually decrease the dose over time in order to completely stop the medication.
A special type of NSAID called a COX2 inhibitor was recently developed to avoid many of these adverse side effects. However, questions about increased risk of stoke and heart attack has caused two of these medications, Vioxx and Bextra, to be removed from the market.
Acetaminophen (Tylenol) is another popular pain medication that is easily obtained without prescription. It is used to reduce pain and fever. It is considered the first line medication for osteoarthritis. It is often used in combinations with prescription drugs including opioids, as in the case of Tylenol 3 and Vicodin. Liver damage is the biggest risk of chronically using or taking too large a dose of acetaminophen. Signs and symptoms of liver damage include abdominal pain, yellowing of the skin or eyes, and nausea or vomiting.
Opioids are powerful narcotic pain medications available only by prescription. Examples of opioids are morphine, methadone, oxycodone, and codeine. Familiar trade names are OxyContin, Vicodin, and Percocet. The three most common side effects of opioids are constipation, nausea and sedation. Other potential side effects are difficulty with concentration and other mental tasks, lack of coordination, urinary retention, itching, and swelling.
The long-term use of increasing amounts of opioids can cause more severe problems and side effects. Physical and psychological tolerance may result from regular opioid use, requiring increased amounts of opioids to relieve pain or control the desire for opioids. This can result in a steady progression of opioid use without pain relief. In fact, long-term use of opioids can lead to a phenomenon known as "opioid induced abnormal pain sensitivity". When this occurs, the opioid user actually experiences increased pain sensitivity with regular opioid use. This can lead to a downward spiral of taking more opioids for pain relief, experiencing more pain sensitivity, then taking more opioids, which cause more side effects.
Another problem with long-term opioid use is its effect on hormonal levels. Hormonal changes can cause decreased sex drive, tiredness, and changes in a woman’s menstrual cycle, and galactorrhea (secretion of breast milk in men or in women who are not breast feeding). Studies have shown that testosterone levels decrease in men and estrogen levels decrease in women receiving high dose opioid therapy.
The immune system is also affected by regular opioid use as the sudden withdrawal of opioids appears to decrease the function of the immune system. This can be a significant problem for immunocompromised people, such as those who have had organ transplants or are suffering from HIV.
Adjuvant analgesics are medications used for pain relief which are primarily used for other health problems. They are usually prescribed with other pain medications. The two main classes of adjuvant analgesics are anticonvulsants and antidepressants. They are generally used to help with nerve pain. Many are also sedating and help with sleep. Other adjuvant analgesics are used "off label", that is they are not specifically FDA-approved for pain.
Some popular FDA-approved anticonvulsants for pain include:
The potential side effects from anticonvulsants include the development of seizures, liver damage, glaucoma, swelling, sedation, and difficulty with thinking and concentration.
- carbamazepine (Tegretol), used for trigeminal neuralgia
- gabapentin (Neurontin), used for postherpetic neuralgia
- pregabalin (Lyrica), used for diabetic peripheral neuropathy/postherpetic neuralgia
Duloxetine (Cymbalta) is the only antidepressant which is FDA-approved for pain. It is used specifically for diabetic peripheral neuropathy. Antidepressants have been known to cause low or high blood pressure, seizures, sedation, problems with heart rhythm, weight gain, urinary retention, tremor, blurred vision, and sexual dysfunction.
In summary, pain medications can have a variety of adverse effects that can become greater when they are used regularly or over an extended period of time. It is important to only take those medications prescribed by a qualified physician or healthcare practitioner, and to take them as they are directed to be taken. If medications are obtained over-the-counter, it is very important to read and follow the directions that come with them, no matter how harmless they may seem. Unfortunately, many people die or develop liver failure from taking too much acetaminophen.
Using medications inappropriately or in combination with other drugs, including street drugs, or alcohol, can result in serious health consequences. It is important to review all medications and health problems with your physician. Being informed about the specific side effects associated with your pain medications can increase your chances of avoiding severe health problems, and lead to a better treatment outcome for your pain.