What should I know about analgesics?

An analgesic is a medication that primarily relieves pain. There are several types of analgesics, including nonsteroidal anti-inflammatory drugs called NSAIDs. They all work in different ways.

Both acetaminophen and aspirin, which is an NSAID, are used to relieve the pain of mild to moderate headaches. They are commonly combined with caffeine. Caffeine has some pain-relieving action and also aids in getting more aspirin into the bloodstream.


Other NSAIDs, such as naproxen, are used to treat both tension-type and migraine headaches. With migraines, they can reduce the pain of an attack and end an attack sooner. Naproxen is often the first choice for treating migraine headaches. Several studies have shown it is effective, has few side effects, and is generally safe to use.

Stronger analgesics, including narcotics, can relieve more severe pain. However, they also have more serious side effects. For this reason, they are usually reserved for the more severe headaches.

Your response to one type of analgesic may not be the same as someone else's. Also, your response will vary from type to type and even from one medicine to another of the same type. Therefore, choosing a medication that works for you may involve trying several different types before the right one is found.

Most NSAIDs are taken by mouth. However, other forms are available. Indomethacin, for instance, can be taken as a rectal suppository. Ketorolac can be found in a cartridge needle unit for self-injection into the muscle. Do not take more than the recommended maximum dosages of NSAIDs.

When you take aspirin or acetaminophen, you need to observe the following cautions:

  • Do not take more than 1,000 mg of aspirin or acetaminophen at the time of a headache.
  • Do not take more than 4,000 mg of aspirin or acetaminophen a day.
  • Do not use aspirin or acetaminophen more than 3 days a week. Both can cause rebound headaches if they are used more than that.

These are the maximum recommended dosages. Exceeding these can cause liver, kidney, or stomach problems.

How do analgesics work?

Aspirin and NSAIDs reduce pain, mostly by blocking inflammation-causing chemicals, such as prostaglandins, that are associated with pain. Acetaminophen also blocks pain without reducing inflammation. Combination analgesics that combine aspirin or acetaminophen with barbiturates or narcotics can provide greater pain relief than can either agent alone. These are available only by prescription, are habit forming if used regularly, and are usually only used for severe headaches.


Side Effects and Drug Interactions

What are the possible side effects from using analgesics and what should I do about them?

The following side effects are not generally serious. Still, you should check with your doctor if any of them occur while you're taking analgesics:

  • constipation
  • diarrhea
  • dizziness
  • drowsiness
  • headache
  • insomnia
  • nausea or vomiting
  • rash or itching
  • tinnitus or ringing in your ear
  • upset stomach

Other more serious side effects can occur while you're taking analgesics. You should get the advice of your doctor if any of the following occur:


  • you develop ulcers
  • you experience gastric bleeding, which can cause you to have black or bloody stools or to vomit blood or dark material
  • you experience a worsening of kidney disease

What drugs may interact with analgesics and what other health conditions might create a problem?

Talk with your pharmacist and your doctor about possible drug interactions with analgesics. Be sure you tell your doctor and pharmacist about all the other medications you take. Tell them also about any other medical conditions you have, such as high blood pressure or asthma. It is also important to keep your regular appointments so your doctor can monitor your progress while you take these medications.

Analgesics can have serious adverse effects if you are taking any of the following. So let your doctor and pharmacist know if you are taking:

  • anticoagulants such as coumadin
  • asthma medications
  • some medications for ulcers
  • cimetidine
  • some blood pressure medications
  • some heart medications, including digoxin
  • medications for seizures such as phenytoin or lithium


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