A man whose daily cluster headaches felt like a smoldering ice pick in his eyes says he found relief after taking LSD

• A man with "almost unbearable" cluster headaches was contemplating euthanasia until he took LSD in a trial.
• Jeffry Bader tried more than 12 treatments before LSD, but nothing stopped the pain.

A man whose agonizing cluster headaches got so bad he contemplated euthanasia said that he found relief after taking the illegal psychedelic drug LSD in a clinical trial.

"It's an almost unbearable pain. As if a smoldering ice pick were stuck into the back of your eyes," Jeffry Bader, 30, said of his daily cluster headaches in "How to Change Your Mind." His words were translated by the makers of the Netflix documentary, which explores the use of mind-altering drugs to treat medical conditions that don't always respond to existing therapies, such as cluster headaches.

Cluster headaches are near-daily bouts of excruciating pain, typically experienced behind the eye, that reach maximum intensity within fifteen minutes and generally last one to three hours. For most people with cluster headaches, attacks last between a month to 12 weeks, followed by months or even years of respite. But around a fifth of patients, such as Bader, have chronic cluster headaches where there is no pain-free period.

Bader said he got "attacks" of pain every day, sometimes up to eight times per day, leading him to lose his hair. The pain was so bad that Bader was unable to work.

Anyone can get cluster headaches, but they tend to affect men more than women. There's currently no cure for this rare and potentially debilitating condition that affects fewer than 1 in 1,000 people. Treatments include oxygen therapy at the time of the attack, and medications that either relax blood vessels, reduce inflammation, or are prescribed to prevent headaches by restoring the balance of certain brain chemicals.

Scientists studying LSD have said there are reports it reduces the frequency and severity of cluster headache attacks, and can stop symptoms from happening, though this isn't yet proven.

Bader tried everything from antiepileptic medication to ketamine for his headaches

Bader first experienced "strange headaches" when he was a child, but they weren't that intense of frequent.

Bader told Insider that the first cluster headache attacks started when he was around 14 or 15 and became daily from then on. He was diagnosed with chronic cluster headaches around ten years later, which was when he was first given treatment.

Since then, Bader has tried more than 12 treatments, from antiepileptic medications to ketamine infusions.

But nothing stopped the pain.

"In Switzerland we have an institution called Exit, where you can choose suicide. And that always remains a realistic thought to me. To what extent is life worth living?" Bader told journalist Michael Pollan in the documentary, which was inspired by his book "How to Change Your Mind."

According to Brain Research UK, the pain caused by cluster headaches is so bad that suicidal tendencies are often reported among patients, earning them the name "suicide headaches."

Bader has had 5 pain-free days after he took LSD

Bader took LSD under supervision in a clinic three times in three weeks as part of a trial to test whether the drug can treat cluster headaches.

Bader said in the documentary that since the LSD trial, he'd had at least five days without a cluster headache.

He told Insider his LSD experience gave him "a new joy of life" and is taking steps to see if he can work again.

"It's not that I am magically healed now, but I am able to participate in life again," he said.

Describing his trip to Insider, Bader said he felt "carefree and light" and "could feel like a child for a few hours without any worries or problems."

He said: "My self-pity dissolved into thin air and everything was simply beautiful for a moment. I could see the little things in life again, feel them as beautiful, like the lush green leaves on the tree, how they moved in the wind."

The trial that Bader participated in is ongoing, and it's too early to tell if it was the LSD that caused his symptoms to improve. Some people with cluster headaches can get remissions that last months or years anyway. The drug will also need to be proven safe and effective treatment in further studies before regulators give it the greenlight for doctors to prescribe it.

But Bader is "definitely convinced" that it was the LSD that improved his cluster attacks.

"This opportunity gives me a lot of hope for the future," he said.