You might have sleep apnea.
Sleep apnea, a potentially serious condition that causes people to repeatedly stop breathing during their sleep, can cause you to wake up with a headache. The headache is due to lack of oxygen and increased pressure that can develop in your head due to the condition, Vernon Williams, M.D., sports neurologist and director of the Kerlan-Jobe Center for Sports Neurology and Pain Medicine at Kerlan-Jobe Institute in Los Angeles, tells SELF.
Unfortunately, it can be tough to know if you have sleep apnea on your own, but if your partner complains that you snore a lot, you often feel tired even though you got enough sleep, and you’re having morning headaches, it’s time to talk to your doctor, Dr. Williams says.
Maybe you’re going through caffeine withdrawal.
This normally happens in people who have multiple cups of coffee throughout the day, but it can happen to anyone, Dr. Williams says. Caffeine may impact blood flow to the brain, Dr. Sachdev says, and if you don’t have as much as usual it can cause neurological side effects that are similar to withdrawal from other drugs like alcohol. A big part of that: A raging headache. And, since many people drink coffee in the morning, it can come on first thing.
To compact caffeine withdrawal headaches, Dr. Kriegler recommends trying to avoid caffeine in the afternoon. If you’re trying to go caffeine-free but could do without the headache, wean yourself off slowly. She recommends having ¼ cup decaf with the rest regular, and gradually decreasing how much caffeine you have over time.
In rare cases, it could be something more serious.
When people describe morning headaches, Dr. Williams says it gets his attention because there’s a chance it could be due to something potentially serious, like increased pressure from a brain tumoror mass. People with brain tumors often wake up early with a headache because cerebrospinal fluid pressure is the highest in the early morning, Dr. Kreigler says. “If the tumor is causing swelling, this will stretch the coverings of the brain and cause headaches,” she explains.
This is obviously rare and not the most likely cause of morning head pain, so don't freak out and assume the worst. If you did have a brain tumor, Dr. Williams says you’d probably also experience symptoms like changes in vision, loss of vision, changes in balance, feelings of drowsiness, and changes in your mental status. It's much more likely that your morning headaches are caused by something much less serious.
The bottom line: If you occasionally wake up to a headache, it’s probably no big deal. But if it happens regularly, talk to your doctor so you can find out what's causing them—and fix it.
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