Mood stabilizer
A class of medication used to reduce the highs and lows of bipolar disorder.
A mood stabilizer is a class of medication used in bipolar disorder to reduce the height of the highs and the depth of the lows, and to make episodes less frequent. The useful image is a floor under the lows and a ceiling over the highs — not a switch that turns feelings off.
What they’re for
Two jobs, and they aren’t the same. Some of the work is acute: settling an episode that is already happening. Most of it is preventive: making the next episode less likely, or smaller. That second job is why they’re usually taken when you feel fine, which is the part people find hardest to keep doing.
Common examples
Lithium is the longest-established and the most studied. Lamotrigine is used more on the depressive side. Several anticonvulsants and some antipsychotics are also used as stabilizers — the categories overlap more than the names suggest.
These medications interact with other things — other drugs, hormonal contraception, dehydration, even how much salt and fluid you take in — which is why a prescriber needs the full list of what else you take.
What to expect
They rarely work overnight. Settling an episode is measured in weeks; judging whether something prevents the next one takes months. Finding a fit often takes more than one attempt — which is exhausting and normal rather than a sign that nothing will work.
Some require regular blood tests — lithium levels and kidney and thyroid function, for example — and that isn’t a formality: it’s how the dose stays in a safe range. Some carry specific warnings worth knowing about, such as the slow, careful dose schedule lamotrigine needs because of the risk of a serious rash. A new rash, a fever, or feeling unwell after a dose change is a reason to contact your prescriber the same day rather than wait for the next appointment.
Pregnancy
Some stabilizers carry serious risks in pregnancy — valproate most of all, and lithium requires specific planning. This matters before conception, not after, and it applies to anyone who could become pregnant. It is a conversation to have with a prescriber early, not a reason to stop anything on your own. See bipolar and pregnancy.
The rule that doesn’t change
Never start, stop or change a medication on your own, and never double a dose to replace one you missed. If you miss a dose, ask your prescriber or pharmacist what to do — the answer is different for different medications.
Stopping a stabilizer abruptly is one of the most common ways an episode gets triggered; the evidence is strongest for lithium, where a sudden stop can bring a high back quickly. This page is educational and deliberately gives no doses: which medication, how much and for how long are decisions for the person who prescribes it, who knows your history and your labs.
See also
If you’re in crisis or thinking about harming yourself, you’re not alone and help is available right now. In the US & Canada call or text 988. In the UK & Ireland call 116 123 (Samaritans). Elsewhere, contact your local emergency services — Get Help Now lists lines by country.
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