Lamotrigine
A seizure medicine that also prevents bipolar depression. Usually easy to take, as long as it’s started slowly.
Quick answer: Lamotrigine treats epilepsy and helps prevent depressive episodes in bipolar disorder. It must be started at a low dose and increased slowly over about 6 weeks, because going too fast raises the risk of a rare, serious rash. Any new rash in the first 2 months needs a same-day check. The combined pill lowers lamotrigine levels, and valproate doubles them.
At a glance
- For
- Epilepsy; preventing depression in bipolar disorder
- Works
- Good seizure control for many; better at preventing bipolar lows than highs
- Cost
- $25 a script on the PBS for epilepsy ($7.70 concession); other uses private, usually cheap as a generic
- Kicks in
- The dose build-up takes about 6 weeks; mood benefit builds over months
- Dose
- Slow build-up from 25 mg; halve the steps with valproate; higher doses with the combined pill or some seizure medicines
- Watch for
- Any rash in the first 8 weeks, dizziness, double vision, headache, nausea
The tortoise of mood stabilisers: start slow, never rush, never restart at full dose after a break.
Brand names
- Lamictal, Lamidus, and generic lamotrigine brands
How it works
Lamotrigine calms overexcited nerve cells by blocking sodium channels and reducing glutamate release. That steadies the electrical storms of epilepsy and, through less understood ways, smooths out depressive swings in bipolar disorder.
Used for
- Epilepsy: focal and generalised seizures, including Lennox-Gastaut syndrome (TGA-approved)
- Bipolar disorder: preventing depressive episodes (TGA-approved)
- Off label: sometimes added for treatment-resistant depression, borderline personality emotional swings, or nerve pain; evidence is limited
Side effects
Most people tolerate it well. Headache, dizziness, double vision, tiredness and nausea are the common ones. A harmless rash affects up to about 1 in 10, but because a rash can also be the first sign of a rare, dangerous reaction, any rash needs a check.
Full side-effect list (from the product information)
How often, from the official product information. Bold = serious.
Very common more than 1 in 10
- Headache
- Rash
Common 1 in 10 to 1 in 100
- Dizziness, unsteadiness or tremor
- Double or blurred vision
- Sleepiness or trouble sleeping
- Nausea, vomiting or diarrhoea
- Tiredness
- Irritability or aggression
- Joint or back pain
Rare 1 in 1,000 to 1 in 10,000
- Stevens-Johnson syndrome (adults about 1 in 1,000; higher in children)
- Aseptic meningitis
- DRESS (rash, fever, swollen glands, liver or blood changes)
Very rare fewer than 1 in 10,000
- Toxic epidermal necrolysis
- HLH (a severe immune reaction with fever and rash)
- Liver failure
- Blood count problems
Get help urgently if
- Any rash, especially with fever, mouth or eye sores, blistering or peeling: stop and seek help the same day
- Fever with swollen glands, sore throat or feeling very unwell
- Severe headache with neck stiffness and fever
- Thoughts of self-harm. Call 000 or Lifeline 13 11 14
Good to know
- Missed more than 5 days? Don’t restart at your usual dose. Ask for a new build-up plan.
- The combined pill roughly halves lamotrigine levels; levels bounce back in the pill-free week. Your doctor may adjust the dose.
- Valproate roughly doubles levels, so the dose is halved. Carbamazepine, phenytoin and rifampicin lower levels.
- Pregnancy: one of the safer seizure medicines. Levels fall in pregnancy, so plan with your doctor; take folic acid.
- Don’t stop suddenly if you have epilepsy.
Common questions
Why does lamotrigine have to be started slowly?
Going up slowly over about 6 weeks lowers the risk of a rare but serious rash such as Stevens-Johnson syndrome. Starting too high, or adding it to valproate without halving the dose, raises the risk.
What does a lamotrigine rash look like?
Most rashes are mild, but any rash in the first 2 months needs a same-day check. Warning signs are fever, blistering, peeling, mouth or eye sores, or feeling unwell.
Does the pill affect lamotrigine?
Yes. The combined pill roughly halves lamotrigine levels, which can mean breakthrough seizures or low mood. Levels rise again in the pill-free week. Your doctor may adjust the dose.
Information only. Not a recommendation or endorsement of any product. Whether a medicine suits you depends on your health and other medicines, so talk to your doctor or pharmacist. In an emergency, call 000 (Australia) or your local emergency number. From a mobile, 112 works in most countries.
More information
maladywise.com/medicines/lamotrigine/