People with bipolar disorder experience significant changes in mood, sometimes feeling very high and other times very low.

It is a serious mood disorder which affects about one in fifty people in the UK.

In the COMBINER trial we are studying two medications that are already widely used to help manage bipolar disorder: lithium and quetiapine.

Some people take them individually, others may take them together.

We don’t know which approach works best.

The COMBINER trial will compare them to find out.

If you agree to take part, you will be asked to sign a consent form.

At your first visit we will collect some information about you and your medical history.

We will carry out some simple health checks.

You may be asked to give a blood sample.

You may need an ECG heart test, depending on when you last had one.

You will be asked to complete a questionnaire about your mental health and general well being.

We will also ask you some questions in the form of a research interview.

If you are female and could become pregnant a urine pregnancy test will be required as you cannot take part if you are pregnant or planning to get pregnant.

At each visit we will check that you are keeping to your contraception.

Once your doctor confirms you are eligible you will be randomly allocated one of three treatments: lithium, quetiapine, or both together.

If you are allocated to both together they will start a month apart.

Your doctor will prescribe your allocated treatment, to collect and take at home.

We will follow up every three months for two years.

Sometimes face to face, sometimes remotely.

At each follow up we will ask you to complete the research interview by phone or video call.

We may ask you to complete an online questionnaire.

Your blood pressure, height, weight and waist measurements will be taken every 6 months.

We may also ask you to provide a blood sample during this visit.

At 12 and 24 months you will have a treatment review at the clinic where you joined the trial.

If you are taking lithium we will check your blood regularly, starting with weekly tests.

Once your levels are stable, the tests will be done every three months.

If you are taking quetiapine, your blood will be checked every three months.

With both medicines some people might experience side effects, which we will monitor with you.

Taking part is voluntary and you can leave at any time without giving a reason.

Your standard care will continue.

We will reimburse you for completing your follow up assessments.

Taking part will help us to improve the treatment of bipolar disorder.

If you have any questions, please talk to a member of the research team.