Headaches are a common health complaint, occurring across all ages and in both genders. In 1984, a study published in the “Journal of the American Medical Association” looked at the effectiveness of caffeine used in addition to analgesics. After examining 30 clinical studies, researchers concluded that caffeine increased the pain-relieving capacity of analgesics by 40 percent. Caffeine continues to be a common addition to headache formulations today.
Changes in blood vessels, nerves or brain chemicals all possibly cause headaches. Many different types of headaches are recognized. Tension headaches are the most common, with pain occurring on both sides of the head. Migraine headaches often cause visual disturbances, can be debilitating and occur more often in women. Cluster headaches occur more often in men; the severe pain comes on suddenly and tends to localize around one eye.
Caffeine is a central nervous system stimulant that is rapidly absorbed by your body. The liver metabolizes caffeine, and it is excreted in your urine. Caffeine is useful for increasing mental alertness and holding off fatigue and drowsiness. Doctors prescribe caffeine citrate to treat breathing problems in premature infants. Caffeine is a methylxanthine with a complex metabolic action. It inhibits prostaglandin synthesis, affects the movement of intracellular calcium and inhibits the release of histamine from mast cells.
Caffeine in Analgesics
By itself, caffeine can relieve the pain of tension headaches. Some migraine patients report that coffee can stop migraine attacks, according to the American Headache Society. When added to pain relievers such as aspirin or acetaminophen, caffeine boosts the effectiveness of the pain medicine. In effect, caffeine makes the painkiller more effective than it would be on its own. One study comparing caffeine and acetaminophen found that caffeine was more effective than placebo and as good as acetaminophen at relieving tension headaches, notes AHS. The pain-relieving effect of caffeine may be due to its ability to block adenosine receptors in the brain. Brain levels of adenosine increase during migraine attacks. Alternatively, it could be an amalgamation of all the metabolic effects of caffeine that allow it to modulate pain.
Some people are particularly sensitive to caffeine and even small doses can cause symptoms of heart palpitations, irritability and insomnia. The amount of caffeine in analgesics may be enough to create these symptoms. AHS reports that caffeine withdrawal symptoms can occur with as little as 100 mg per day for seven days. This caffeine dosage is obtainable with recommended dosages of some over-the-counter pain medications. However, if you regularly drink coffee or tea, your caffeine tolerance will be much higher and the amount of caffeine found in headache medications is unlikely to cause these symptoms.