Keppra (levetiracetam) causes psychiatric side effects in roughly 13% of adults who take it, making mood and behavior changes the most common reason people consider it “bad.” These effects, which range from irritability to depression, are real and well-documented. But whether Keppra is truly bad *for you* depends on how your body responds to it, what alternatives exist, and whether the side effects can be managed. Here’s what you should know about the specific risks.
Mood and Behavior Changes
The side effect that gives Keppra its reputation is sometimes called “Keppra rage.” About 13.3% of adults on the drug experience psychiatric side effects, though only around 0.7% develop severe symptoms like significant depression, agitation, or hostility. The rest fall somewhere on a spectrum of increased irritability, shorter temper, anxiety, or emotional flatness that can be hard to pin down at first. You might not recognize the change in yourself before the people around you do.
Children tend to be more vulnerable. Behavioral problems and excessive sleepiness are the most frequently reported side effects in younger patients. Parents often describe personality shifts: a previously easygoing child becoming defiant, tearful, or aggressive within weeks of starting the medication.
These changes can appear at any point during treatment, not just at the beginning. Some people tolerate Keppra well for months before mood symptoms emerge, particularly after a dose increase.
Suicidal Thoughts: The FDA Warning
All seizure medications, including Keppra, carry an FDA black box warning about suicidal thinking and behavior. Pooled data from 199 clinical trials covering 11 different seizure drugs found that patients on these medications had roughly twice the risk of suicidal thoughts compared to those on placebo. In concrete terms, that translates to about one additional case of suicidal thinking or behavior for every 530 patients treated.
The absolute risk is low (0.43% on medication vs. 0.24% on placebo), but it’s not zero. This risk appears to apply broadly across all seizure medications regardless of how they work, so switching to a different drug doesn’t necessarily eliminate it. What matters is being aware of it and having people around you who know to watch for warning signs like withdrawal, worsening mood, or talk of hopelessness.
How Keppra Works Differently
Most seizure medications work by calming overactive nerve signaling in fairly well-understood ways. Keppra does something unusual: it binds to a protein called SV2A that sits on the tiny sacs (vesicles) your brain cells use to release chemical messengers. When Keppra locks onto SV2A, it essentially jams the protein in a closed position, reducing the release of those messengers. This is effective at preventing seizures, but because it broadly dampens neurotransmitter release rather than targeting a single chemical pathway, it can affect mood regulation, energy, and cognition in ways that are harder to predict.
Fatigue and Cognitive Fog
Drowsiness is one of the most common complaints, especially in the first few weeks. Many people describe feeling mentally “dulled” or slower than usual, struggling to find words or stay focused. This effect often improves as your body adjusts, but for some people it persists at higher doses.
Interestingly, the cognitive picture isn’t entirely negative. A clinical trial in patients with Alzheimer’s disease found that four weeks of Keppra treatment actually improved spatial memory performance in those who had underlying seizure-like brain activity. This doesn’t mean Keppra sharpens thinking in healthy brains, but it does suggest its cognitive effects are complex and partly depend on what’s happening neurologically underneath.
Kidney Processing and Organ Impact
Unlike many seizure medications that are processed by the liver, Keppra is cleared primarily through the kidneys. This is actually one of its advantages: it’s gentler on the liver and has fewer drug interactions than older seizure medications. But it means your kidneys matter. People with reduced kidney function need lower doses, and those on dialysis require careful scheduling of their medication around treatment sessions.
If your kidneys are healthy, Keppra doesn’t appear to damage them over time. The concern is mainly for people who already have kidney disease and may accumulate too much of the drug in their system, intensifying side effects.
Drug Interactions
Keppra has a relatively clean interaction profile compared to older seizure drugs, but a few medications still require attention. Other seizure medications like carbamazepine, lamotrigine, phenytoin, and phenobarbital can all affect or be affected by Keppra. Methotrexate (used for arthritis and some cancers) and macrogol (a common laxative) also interact. If you’re on any of these, your dose may need adjusting.
Pregnancy Risks
Keppra is often considered one of the safer seizure medications during pregnancy, but “safer” is relative. Data from the Levetiracetam Pregnancy Registry found that 9.4% of infants exposed to Keppra alone during pregnancy had major birth defects. That rate rose to 12.6% when mothers were taking Keppra alongside other seizure medications. For context, the general population rate of major birth defects is roughly 3%. These numbers make Keppra lower-risk than some alternatives like valproate, but the risk is still meaningfully elevated.
Why You Can’t Just Stop Taking It
One of the most important things to understand about Keppra is that stopping abruptly is dangerous. People with epilepsy who have been seizure-free for two years or more still face a real risk of seizures returning if they discontinue the medication. The American Academy of Neurology notes that in rare cases, the drug may no longer work if someone stops and then tries to restart it. Any discontinuation needs to be gradual, done under medical supervision, with a slow taper rather than a sudden stop.
Vitamin B6 as a Partial Fix
A strategy that some neurologists use for Keppra-related irritability is supplementing with vitamin B6. In a study of veterans taking 2,000 mg of Keppra daily, adding 100 mg of B6 per day improved irritability in 45% of patients. The other 55% saw no change. It’s not a guaranteed solution, but given that B6 is inexpensive and low-risk, it’s a reasonable first step before considering a medication switch. The typical dose used in practice is 100 mg once daily.
Weighing the Trade-Offs
Keppra’s side effect profile is real and sometimes severe, but the reason it remains one of the most widely prescribed seizure medications is context. It works broadly across seizure types, has fewer dangerous drug interactions than most alternatives, is easier on the liver, and carries a lower risk of birth defects than several other options. For many people, the side effects are mild or manageable. For others, particularly those who develop significant mood changes or persistent fatigue, the costs genuinely outweigh the benefits, and a different medication is the better choice.
The key is recognizing that “bad” side effects from Keppra are common enough that they should be actively monitored for, not dismissed. If you’re noticing personality changes, persistent anger, deep fatigue, or emotional numbness that started after beginning or increasing Keppra, those are recognized effects of the drug, not something you need to just push through.