Although anticonvulsants are generally used to treat seizures, they have also been proven effective at treating pain, especially pain caused by nerve damage. It is believed that these drugs work by reducing the ability of nerves -- especially damaged nerves -- to transmit pain signals. Carbamazepine, for example, prevents nerves cells from firing repeatedly.
- Examples: These include Tegretol (carbamazepine), Klonopin (clonazepam), Topamax (topiramate), Neurontin (gabapentin), Gabitril (tiagabine), Lyrica (pregabalin) and Valium (diazepam).
- Best for Treating: Pain caused by postherpetic neuralgia (nerve pain from shingles), trigeminal neuralgia and nerve pain caused by diabetes (diabetic neuropathy).
- Important to Know: Most anti-convulsants are well tolerated, but carbamazepine may have serious side effects, including liver problems and allergic reactions; users should be checked regularly for these and other reactions. It is also teratogenic and contraindicated for pregnant women.
Researchers are beginning to understand the complex cause-and-effect relationship between pain and depression. Antidepressants work by changing the levels and effects of neurotransmitters in the brain. Of the three main types of antidepressants: 1) Tricyclic, 2) selective serotonin reuptake inhibitors (SSRIs) and 3) selective serotonin norepinephrine reuptake inhibitors (SSNRIs), tricyclics are most commonly prescribed for pain. However, SSNRIs like Cymbalta (duloxetine), have also been proven successful for certain kinds of pain, like that associated with peripheral neuropathy.
- Examples: These include Prozac (fluoxetine), Paxil (paroxetine), Zoloft (sertraline), Elavil (amitriptyline), Norpramin (desipramine), Effexor (venlafaxine), Sinequan (doxepin), Wellbutrin (bupropion), Serzone (nefazodone), Desyrel (trazadone) and Cymbalta (duloxetine).
- Best for Treating: Migraines, menstrual pain, peripheral neuropathy, diabetic neuropathy, fibromyalgia, back pain and postherpetic neuralgia.
- Important to Know: Most antidepressants take several days or weeks to begin working; for this reason, they may be prescribed with another painkiller like an nonsteroidal anti-inflammatory drug (NSAID). Doses of antidepressants used to treat pain are often lower than doses to treat depression.
The three types of medication prescribed for migraines -- triptans, ergots and isometheptene -- are called abortive medication because, taken early enough, they can prevent a migraine or significantly lessen the associated pain. These medications work by constricting blood vessels, particularly the temporal arteries, thereby relieving pressure on the brain.
- Examples: These include Imitrex (sumatriptan), Zomig (zolmitriptan), Maxalt (rizatriptan), Amerge (naratriptan), Axert (almotriptan), Frovalan (frovatriptan), Midrin (isometheptene, dichloralphenazone, acetaminophen) and Ergomar, Wigraine, Cafergot, Migranal (ergotamine) medications.
- Best for Treating: Migraines, but the pain can be aborted if the medication is used at the initial onset of migraine symptoms.
- Important to Know: Triptans have been associated with serious side effects, including heart attacks and strokes; they may also interact poorly with other drugs, including SSRIs and Tagamet (cimetidine).
Corticosteroids work by reducing inflammation; they are usually prescribed in low doses to minimize the risks of side effects. Prescription-strength corticosteroids may be taken orally, by injection, with an inhaler, or as a topical cream.
- Examples: These include Deltasone (prednisone), Hydeltrasol (prednisolone) and Solu-Medrol (methylprednisolone).
- Best for Treating: Pain and inflammation associated with rheumatoid arthritis and lupus.
- Important to Know: Chronic oral orticosteroids are associated with potentially serious side effects, including weight gain, glaucoma, cataracts, high blood sugar, ulcers, fluid retention, mood swings, suppressed immune systems and increases in blood pressure and osteoporosis.
Cox-2 inhibitors are NSAIDs that are less likely to cause gastrointestinal upset than other types of NSAIDS, like aspirin, ibuprofen and naproxen. Cox-2 inhibitors work by blocking the production of cyclo-oxygenase-2, an enzyme that leads to inflammation and pain.
- Example: The only Cox-2 inhibitor currently available in the US is Celebrex (celecoxib).
- Best for Treating: Arthritis and menstrual pain.
- Important to Know: In 2004, Vioxx (rofecoxib) -- a COX-2 inhibitor manufactured by Merck -- was removed from the market because of its association with heart attack and stroke. Celebrex may pose similar risks.
Opioids were originally derived from the poppy plant; today, opioids are available in organic and synthetic forms. They are also available combined with other painkillers, like ibuprofen and acetaminophen. Because opioids are narcotics with sedative effects, they are sometimes prescribed with stimulants.
- Examples: These include several brands of morphine, Codeine (codeine phosphate), Actiq (fentanyl citrate), OxyContin (oxycodone) and Vicodin (hydrocodone with acetaminophen).
- Best for Treating: Acute pain, such as the type of pain that may be experienced after surgery or severe injury or severe pain due to metastatic cancer.
- Important to Know: Opioids have the potential to be addictive, but when used as directed for short-term pain, this risk is significantly reduced. Side effects may include constipation, nausea, drowsiness and breathing problems.
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