If you're all too familiar with the unbelievable pain of cluster headaches, then you know...

1. It's the worst kind of headache.

All sufferers of cluster headaches—and their doctors and loved ones—agree: The pain is brutal. This unique syndrome is so intense that in the throes of an attack, you might bang their head against the wall or even pull your hair out. The attacks are usually focused on one side of the head, and the pain is often a piercing sensation in the eye or temple, which is why some people refer to them as "ice-pick headaches." The attacks can occur daily (or even multiple times a day) for a few weeks or months; about 1.4 million Americans suffer from them, according to the American Headache Society.

2. Certain times of day suck more than others.

These headaches can occur like clockwork, literally: Some people experience them within a couple of hours of falling asleep, while others might only experience attacks in the mornings, afternoons, or evenings. For some, the pain can kick in at a frighteningly specific time of day, say at 2:30 pm every day. The headaches can also be seasonal, with the spring or fall signaling the onset of attacks.

3. You need a doctor who 100% gets it.

David Jakle/Getty Images

Although medical professionals once doubted the severity of cluster headaches, most appreciate just how painful and frustrating these maddening attacks can be. Good doctors will work patiently with you to determine the right combination of drugs and behaviors that can limit attacks or ease the severity of the pain. (Doesn't sound like your doc? Here are 10 more signs it's time to dump your doctor .)

MORE: 7 Weird Headache Triggers

4. You don't know what desperation is until you're looking for a treatment.

Living with cluster headaches means being on a continual search for respite. The laundry list of options you'll try is endless—in part because of the frustratingly vague origin of the head pain.

5. There's nothing like the sweet relief of oxygen.

One of the most effective treatments is pure oxygen, which is why many people with cluster headaches keep tanks around the house. According to the Mayo Clinic, inhaling 100% oxygen at a minimum rate of 12 liters a minute can head off an attack. A self-administered shot of a triptan drug such as Imitrex can also help; this class of drugs have been effective for migraines in general, and many people with cluster headaches benefit as well.

6. Home can feel like a prison.

Image Source/Dave Smith/Getty Images

When you're in the midst of a cluster, even leaving the house can be terrifying. You may not have the treatment you need with you should a headache come on, and the pain is so intense there's no way to mask what you're going through. Many sufferers complain of feeling almost agoraphobic.

7. You'll never stop hoping for a cure.

When the headaches keep reoccurring, you may turn to surgery to block nerve signals, implants that can stimulate certain centers in the brain, and even psychedelic drugs (a report in the journal Neurology suggested some patients' headaches cleared up after trying psilocybin mushrooms). Researchers continue to pursue possible cures and new treatments, which you can track at the National Headache Foundation, American Headache Society, and at support group-oriented sites such as ouch-us.org and clusterheadaches.com.

MORE: The 10 Most Painful Conditions