What is lithium?

Lithium is a chemical element found in nature that is sometimes used in medicines to treat certain mental illnesses, such as bipolar disorder. Lithium can treat acute mania, or 'highs', and help with longer-term mood stabilisation.

It's also used in treating some types of depression and other types of mental illness.

If you have a mental illness, your doctor will decide if medication is the right treatment for you. Lithium is just one option.

How does lithium work?

Lithium works by changing the release of chemicals in the brain.

It can take some time to get the dosage right and it may be weeks or even months before it affects your mood. If you take lithium, you will need regular appointments with your doctor to make sure you are not taking too little or too much lithium.

What are the benefits of lithium?

Lithium helps reduce the severity and frequency of mania — the elevated, euphoric end of the mood scale — and may help to treat bipolar depression.

If you have been at risk of suicide, lithium may help reduce these feelings. Lithium also helps prevent manic and depressive episodes occurring in the future. Therefore, your doctor may prescribe it over long periods of time to prevent relapse.

Important things to remember when taking lithium

• Tell your doctor or pharmacist if you have any allergies.
• If you are taking diuretics (water pills), tell your doctor since these may need to be carefully monitored.
• Tell your doctor about any other medicines, supplements or complementary medicines you are taking, as they may interact with lithium.
• If you are pregnant, planning to become pregnant or breastfeeding, tell your doctor straight away. Lithium may cause harm to a fetus or baby.
• Tell your doctor first if you have any heart or kidney problems.
• Lithium can cause drowsiness, so it is important to consider this if driving or operating heavy machinery

What are the side effects of lithium?

Short-term side effects

You may have some short-term side effects when starting treatment with lithium or changing dose. It's important to weigh up these short-term side effects with the benefit lithium may have for the symptoms of the mental illness.

Short-term sides effects can include:

• shaking
• metallic taste
• feeling very tired
• acne
• fatigue
• diarrhoea
• thirst
• frequent urination
• nausea
• vomiting
• headache

These side effects usually go away after a few days. If side effects continue or are worrying you, see your doctor. If they suddenly get worse, it may be a sign of 'lithium toxicity', or too much lithium in your body (see below). If this happens, call your doctor immediately.

Long-term side effects

Taking lithium for long periods can affect your kidneys and your thyroid. Lithium can also cause drowsiness.

Your doctor will carry out blood tests regularly to monitor how much lithium is in your blood. They will also monitor your kidney function, your thyroid gland and your parathyroid gland.

Some people who take lithium for long periods gain weight. A healthy diet and regular exercise can help you keep your weight under control. Talk to your doctor about managing your weight.

Women who take lithium are usually advised to use other medicines while pregnant.

What is lithium toxicity?

You can develop lithium toxicity suddenly if you take too many tablets at once or combine lithium with certain other medicines.

If you are on a steady dose of lithium, you may get chronic lithium toxicity when your kidneys stop working properly.

Lithium toxicity can cause:

• nausea
• vomiting
• diarrhoea
• confusion
• trouble walking
• blurred vision
• muscle weakness
• drowsiness
• flu-like symptoms
• psychosis
• seizures
• coma

If you think you or someone you care for may have lithium toxicity, it's important to talk to a doctor immediately.

See healthdirect's medicines section for more information about lithium.