Caffeine Withdrawal Headaches
Although too much caffeine can cause headaches, the most common cause of caffeine headaches is caffeine withdrawal.
Caffeine withdrawal occurs when you have developed a caffeine addiction and then you suddenly reduce or eliminate your caffeine consumption. Caffeine addiction is not necessarily the result of long-term or high-level caffeine consumption, and can develop in as little as a few days of drinking lattes or other drinks with caffeine. However, most caffeine withdrawal headaches are a result of consuming 500 mg of caffeine or more per day for two weeks or longer before reducing or eliminating caffeine in the diet.
When your body gets used to a certain level of caffeine, you may notice that you experience fatigue and other side effects (such as headaches) until you have reached your typical level of caffeine consumption. (A 2010 study showed that these caffeine withdrawal side effects are reversible... if you simply consume your usual level of caffeine to get rid of them.)
Consuming caffeine as a cure for caffeine withdrawal headaches can be a problem for people who are trying to reduce or eliminate caffeine in their diets, but alternate cures include sleep, massage, acupressure, caffeine-free medication (some headache relievers, like Excedrin and Goody's, contain caffeine) and drinking plenty of water. To avoid getting caffeine withdrawal headaches while cutting down on caffeine, read these caffeine reduction tips. If you're a coffee drinker, be sure to also check out this video tutorial on reducing caffeine in coffee.
Caffeine for Headaches
In addition to quickly curing caffeine withdrawal headaches, caffeine may help cure regular headaches and even migraines.
Some studies have shown that small doses of caffeine taken in conjunction with pain killers may help the body absorb the medication more quickly and cure the headache in a shorter period of time. Although most pain killers begin to take effect within 15 minutes, every minute can make a difference when you're suffering from a particularly bad headache!
Additionally, 130 mg of caffeine taken in conjunction with pain killers has been shown to improve headache relief by approximately 40 percent -- a substantial difference in results. Some people find that they don't need to take as much of a given pain killer when it is taken in conjunction with caffeine, and some doctors advocate taking medications with caffeine to reduce the likelihood of developing an addiction to a given pain killer.
An increase in the speed and efficacy of pain killers are the reasons that some prescription and over-the-counter pain medications contain caffeine. However, it is unclear whether or not caffeine taken without a pain killer is an effective headache cure.
Other Caffeine Headaches
Besides caffeine withdrawal headaches, there are two main types of caffeine headaches: headaches from excess caffeine consumption and 'rebound headaches' / 'medication overuse headaches.'
Headaches from excess caffeine consumption can be cured or helped by drinking peppermint 'tea,' getting a massage, drinking plenty of water and/or taking caffeine-free pain killers. Some people find that consuming food before consuming caffeine can provide a 'cushion' for their caffeine absorption and reduce the chances of a caffeine overdose or headache from too much caffeine consumption. Headaches from excess caffeine can also be avoided by limiting your caffeine intake. (Go figure!)
'Rebound headaches' or 'medication overuse headaches' are a type of headaches caused by overmedicating with pain killers and some related types of medications. The medications can contain caffeine, or not, but the overuse of pain killers and caffeine in conjunction can increase the likelihood of getting a rebound headache when the levels of pain killers and caffeine in your bloodstream are reduced.
You can avoid rebound headaches by taking medications in moderation, or by periodically not taking the medication in question for three consecutive days. You can help cure rebound headaches by drinking peppermint 'tea,' getting a massage, drinking plenty of water and resting.
Read more on caffeine and headaches from About.com's former Guide to Headaches, Mark Foley. Read more on how caffeine withdrawal headaches work on ScienceDaily.