Painkillers: A Guide to What Works

For Migraines

Generic names: Triptans, including sumatriptan (sometimes with naproxen) and rizatriptan.

Common brand names: Imitrex, Maxalt, Treximet

The basics: The pain and other symptoms of a migraine arise from a cascade of events involving the brain chemical serotonin, the trigeminal nerve (responsible for facial sensations), and blood vessels in the brain. These changes trigger the release of pain-producing substances and cause blood vessels to dilate. Triggers may include hormonal changes, stress, certain foods, and more. "Medications called triptans reduce inflammation and constrict the vessels so they go back to their normal size," says Brian Grosberg, MD, co-director of the Montefiore Headache Center in the Bronx, New York. Triptans can also ease the nausea and light sensitivity that accompany a migraine.

The issues: These drugs are most effective if you use them as soon as you feel a migraine coming on. "After the pain has built up, it's harder to treat," says Dr. Grosberg. Potential side effects include nausea, dizziness, muscle weakness, or a sense of warmth or tingling. Don't use these drugs if you have heart disease.

For acute pain after surgery or from an injury, or for serious chronic pain

Generic names: Prescription opioid narcotics have many generic names, including codeine, fentanyl patch, hydrocodone, methadone, morphine, and oxycodone.

Common brand names: Avinza, Kadian, MS Contin, OxyContin, Percocet, Tylox, Vicodin

The basics: Opioids mimic the body's natural pain-relieving endorphins; they bind to nerve receptors so pain messages don't travel to the brain. Opioids also boost levels of the feel-good neurotransmitter dopamine, which improves your ability to tolerate pain.

The issues: Some opioids, like Vicodin and Percocet, also contain acetaminophen and carry the same risk to the liver. Because of that, the FDA decided to phase out prescription medications that have more than 325 mg of acetaminophen per pill (they'll be gone within two years). Opioids can make you nauseous and groggy for the first few days, but you should improve as your body adjusts to them. Because these drugs slow the digestive tract, constipation is often a problem. Opioids also pose a small risk of addiction.

Never combine opioids with alcohol, antihistamines, sleeping pills or anti-anxiety drugs without checking with your doctor first, says Dr. Fishman. Doing so could lead to depressed breathing, which is how the actor Heath Ledger died after he combined two sedatives, two pain-killers, and two anti-anxiety drugs.

For nerve pain, like diabetic neuropathy, and muscle and joint pain

Generic names: Antidepressants and other drugs in that class, such as amitriptyline, desipramine, duloxetine, milnacipran and nortriptyline.

Common brand names: Cymbalta, Elavil, Endep, Norpramin, Savella

The basics: It's a vicious cycle -- being in pain can lead to depression, and being depressed makes you hurt even more. These medicines improve mood and directly target the discomfort. "Antidepressants stabilize the membranes surrounding nerve cells, making the cells less likely to fire when they shouldn't," says Dr. Fishman. That means fewer pain signals are sent to your brain.

The issues: Antidepressants may cause sleepiness, nausea, sexual dysfunction, and jitteriness; sometimes they also blunt your emotions. It's often a matter of trial and error to find one that you can tolerate -- but don't stop taking them without talking to your doctor.