Brain zaps: Why they happen and what to do about them

What are brain zaps?

While there doesn’t seem to be a medical name for this symptom, “brain zaps” has become the unofficial term for the “zapping” sensation that can occur while stopping an antidepressant—specifically SSRIs (selective serotonin reuptake inhibitors) and SNRIs (serotonin-norepinephrine reuptake inhibitors). They can happen whether you intentionally taper off or accidentally miss a dose.

“It is a colloquial term for a variety of symptoms—usually a lightning or electric-shock sensation that feels like it’s coming from inside their head,” says Lisa Schock, M.D., clinical assistant professor and associate psychiatry residency program director at the University of North Dakota School of Medicine & Health Sciences.

Brain zaps are one of many symptoms that can arise when stopping an antidepressant too quickly, also known as discontinuation syndrome. That said, it’s typically preventable and not something everyone should expect, says Kate Hanselman, PMHNP, VP of clinical psychiatry at Thriveworks. “They usually don’t occur when a taper is done at an appropriate speed.” More rarely, they can also happen when starting an antidepressant or adjusting the dose, Hanselman adds.

What do brain zaps feel like?

Brain zaps usually feel like a momentary buzzing, jolting, or shocking sensation. People typically describe them as “a little electric shock in their brain,” Dr. Hanson says. They tend to last a second or less, Dr. Schock adds, though you might experience it a few times in a row.

Brain zaps usually feel like they’re coming from inside your brain, but some people also experience them around the eyes or ears. Less commonly, people can feel them extend to other areas of the body. “I’ve had people experience an electric-shock sensation that seems to go down their spine or a limb,” Dr. Schock says.

The sensation can sometimes be accompanied by other symptoms, like disorientation, brain fog, ringing in the ears, or visual distortions, Dr. Schock says. A 2018 study of 595 online posts describing brain zaps on a mental health forum found that they were most commonly accompanied by a sense of vertigo or hearing a sound (including people who reported feeling like they could hear their eyes move).

Why do brain zaps happen?

Researchers theorize that when you reduce the dose of an SSRI or SNRI too quickly, brain networks that rely on these chemicals can have difficulty adapting to the sudden changes in brain chemistry, causing symptoms like brain zaps. But that’s still a working theory rather than a confirmed mechanism.

“We don’t really understand everything that goes on to cause these brain zaps,” Dr. Schock says. “But it does seem to be associated with changes in neurotransmitter levels.”

SSRIs and SNRIs prevent your brain cells from reabsorbing either serotonin (in the case of SSRIs) or serotonin and norepinephrine (SNRIs) in order to create higher levels of those chemicals in your brain. Over time, the brain adapts to having certain amounts of these neurotransmitters present, Dr. Schock says. When that level drops (like if you miss a dose or taper down too quickly), that can impact how the neurons in your brain signal one another.

There is some evidence that SNRIs are more likely to cause brain zaps than SSRIs, Dr. Schock says, possibly because it involves two different neurotransmitters instead of one.

Brain zaps also tend to be more common with medications with a shorter half-life (meaning they leave the body faster) like venlafaxine (an SNRI) and paroxetine (an SSRI). That same 2018 study found that venlafaxine and paroxetine were the most commonly reported prescriptions among people experiencing brain zaps. People taking venlafaxine can even experience discontinuation symptoms, like brain zaps, if they don’t take their meds on time, Hanselman says.

This happens because these medications wear off pretty quickly, causing much more abrupt changes in neurotransmitter levels than drugs that gradually leave your body. “You essentially have an unintentional fast taper, without trying to, because the medicine just doesn’t stick around as long,” Hanselman explains. “It gets out of your system so quickly that you have that drop.”

Another detail that intrigues researchers is that brain zaps often seem to be triggered by side-to-side eye or head movements, with one 2022 study finding this to be the most commonly reported trigger. “There seems to be a connection there,” Dr. Schock says, “and not a whole lot of information about why that is.”

“We could hypothesize about the way that your optic nerve is connected to the rest of your brain,” Hanselman adds. “But I don’t know.”

Are brain zaps dangerous?

No, brain zaps are not dangerous. “They can really scare people, because they feel scary,” Hanselman says. “But they’re not dangerous. They won’t hurt you.” As disorienting and unpleasant as brain zaps can feel, there is no evidence or reason to believe that they’re endangering your brain.

The surprising reason brain zaps are so understudied

The truth is, there’s a lot we still don’t know about what happens in the brain when we take certain medications, Hanselman says. And because brain zaps are not dangerous and are quickly resolved, they simply aren’t an urgent concern for pharmaceutical companies to research.

“For most people, we can manage and treat these relatively easily,” Dr. Schock says. “So in terms of the dangerousness and the long-term effects, I would say that there’s probably not a lot of incentive to understand and figure out ways to completely mitigate them.”

Hanselman takes solace in the fact that, even when psychiatrists are not sure exactly why something is happening (like brain zaps), they do know how to alleviate them. And that’s what she tells patients who are worried about or experiencing brain zaps: that they aren’t dangerous, they’re thought to be caused by a drop in neurotransmitter levels, and there are ways to manage them.

How to deal if you’re getting brain zaps

The most effective way to lower the risk of brain zaps is to taper antidepressants slowly and carefully, Hanselman says. That’s why providers recommend that you always consult a professional before stopping an antidepressant—so they can help you adjust your dosage gradually and prevent or minimize any symptoms of discontinuation syndrome.

If you find yourself getting brain zaps while intentionally tapering your medication, the recommendation is to go even slower. “There’s no rush,” Hanselman says. That usually looks like slightly increasing the dosage again, and then staying at each step-down in dosage for a bit longer.

In some cases, clinicians may add on or switch you over to a longer-lasting medication as a “bridge” (especially if you’re on a shorter half-life medication). This helps slow down the change in brain chemistry, Dr. Schock explains, giving your brain more time to adjust to the changes in neurotransmitter levels. A popular choice is fluoxetine, Dr. Schock says, since it has the longest half-life among SSRIs. (In the 2018 study, only 3.1% of posts mentioned fluoxetine, despite it being one of the most commonly prescribed antidepressants.)

Let’s say you’re not actually trying to stop your antidepressant but you’re noticing brain zaps whenever you forget to take your dose on time. In that case, it could also be worth switching to a medication with a longer half-life, Dr. Schock says.

If you’re experiencing or concerned about brain zaps, talk to your provider. “A lot of people will suffer through side effects and not bring them up,” Dr. Schock says. “But there are things that we can do, so it’s really important to communicate those things to your provider.”

That’s especially true if the brain zaps are distressing, disruptive, or prolonged—or if you’ve experienced them when tapering off an antidepressant before, Hanselman says. “You don’t have to just white-knuckle it and tolerate them.”

The bottom line

Brain zaps feel strange, but they aren’t dangerous. They often go away on their own, and psychiatrists know how to help you manage them if they’re stubborn or bothersome.

Still, it’s hard to believe that we know so little about such a common phenomenon. Even if a minority of people experience brain zaps while stopping antidepressants, that’s millions of individuals who don’t have a great explanation for what they’re experiencing and why.

For now, the practical move is to taper slowly and loop in your prescriber if symptoms start. “We can slow it down even more,” Hanselman says.

Frequently asked questions (FAQs)

Are brain zaps dangerous?

No, brain zaps are not considered dangerous in any way. “They can be distressing, but you’re not in any danger.” Hanselman says. So as uncomfortable as they can feel, remember that they’re harmless and will resolve over time.

How long do brain zaps last?

It depends on the person, but brain zaps usually last for a few days to a few weeks before going away on their own, Dr. Schock says. If you and your provider adjust the rate of your taper, they should resolve fairly soon after you go back up in your dosage.

Why do brain zaps happen when you miss a dose?

Missing a dose of medication can make the medication levels in your system drop quickly, especially with shorter half-life antidepressants like venlafaxine. That sudden change may trigger withdrawal symptoms, including brain zaps, within a day. “People can miss the dose by a couple of hours and start to experience it if they’re particularly sensitive,” Dr. Schock says.

Do brain zaps mean your medication is not working?

No, brain zaps don’t mean anything about the effectiveness of your antidepressant, Dr. Schock says. “The only thing they can indicate is that you’ve missed a dose or you’re tapering.”

Can brain zaps happen on other medications besides antidepressants?

There aren’t reports of brain zaps happening with other medications. “They seem to be unique to antidepressants,” Dr. Schock says. But other medications that affect neurotransmitters (like stimulants for ADHD) can cause symptoms when you taper off of them.

Will brain zaps go away on their own?

Yes, brain zaps go away on their own within a few days to a few weeks. Dr. Schock says—especially if the taper is happening at a gradual enough pace. If they linger, though, slowing down the taper or adjusting your medication plan can help resolve them.