How and when to take valproic acid

The usual dose of valproic acid for treating bipolar disorder in adults is 750mg to 2,000mg a day, split into 2 or 3 doses.

The usual dose for preventing migraine in adults is 500mg to 1,000mg a day, split into 2 or 3 doses.

The usual dose for treating epilepsy in adults and children aged 12 years and over is 600mg to 2,000mg a day, split into 2 to 4 doses. Some people take a higher dose of 2,500mg a day.

For younger children who weigh more than 20kg, the doctor will use your child’s weight to work out the right dose.

If you need to take your medicine more than once a day, you'll take equal doses that add up to your daily total. Ask your doctor or a pharmacist if you're unsure how much to take each time.

If you're taking valproic acid and have kidney problems, your doctor may prescribe a lower dose.

Changes to your dose

To reduce the chance of side effects, your doctor will start you off on a low dose of valproic acid. They will increase it gradually over a few days or weeks.

Once you find a dose that suits you, it will usually stay the same, unless your condition changes, or your doctor starts you on a new medicine that may affect valproic acid.

How to take it

Valproic acid comes as gastro resistant tablets and capsules. These release the valproic acid into your body as soon as they pass through your stomach.

Swallow the tablets or capsules whole with a drink of water or squash. Do not chew them.

You can take valproic acid with or without food, but it's best to do the same each time.

If you're taking valproic acid twice a day, try to leave a gap of 10 to 12 hours between doses. For example, you could take your first dose in the morning (between 7am and 8am) and your second dose in the evening (between 7pm and 8pm).

If you take it 3 to 4 times a day, try to space your doses evenly throughout the day. If you need to take 3 doses, for example, you could take a dose first thing in the morning, early afternoon and bedtime.