People with manic depression are being urged to demand better medical care.
Two in 100 people suffer from manic depression
The Manic Depression Fellowship says many doctors fail to provide patients with enough information or choice over which drugs they take.
It says this can cause people to stop taking their medication, increasing their risk of committing suicide.
The charity has now published a document outlining the different treatments available so they can demand a better standard of care.
Manic depression or bipolar disorder affects around two in every 100 people in the UK.
However, that figure is beginning to rise as more and more people are being diagnosed with the condition.
It is characterised by extreme mood swings between mania and depression.
Without effective treatment, around 50% of people with the condition will try to commit suicide. As many as one in 10 people will kill themselves.
Drugs to treat the condition are available. However, some of these can have unpleasant side-effects which cause people to stop taking their medication.
Problems arise when they fail to tell their GP that they have stopped taking the drugs.
According to the Manic Depression Fellowship, many patients fail to discuss the issue with their doctor because they are unhappy with the care they have received.
Some are also unaware that alternative drugs are available. Many GPs prescribe older medications and few offer patients a choice of drugs.
The charity's document spells out the different types of drugs available and the evidence behind them.
"We have launched this guidance to give people with bipolar disorder the information and confidence they need to ensure the care they receive is of the best possible standard," said Amanda Harris of the Manic Depression Fellowship.
"We know that if people with bipolar disorder are unhappy with their treatment there is a high risk they will stop taking their medication, often without informing their doctor.
"By making this crucial information easily available, we hope to lessen the burden the bipolar disorder places on peoples lives."
Professor Mary Phillips of the Institute of Psychiatry in London said the problems were centred on the fact that doctors were prescribing drugs to treat the manic side of the illness.
As a result, patients are being offered a very limited choice of drugs.
This is despite the fact that most patients are generally depression for much longer than they are manic. In addition, they are also more likely to try to commit suicide when they are depressed.
Professor Phillips said there is a need for new drugs to treat both aspects of the condition.
"Although many people are managing on the older medications there is a need for a treatment that is specifically licensed to prevent depression without increasing the risk of switch to mania," she said.
The Manic Depression Fellowship's guidelines, called Drug Treatment for Manic Depression, are available from the charity on tel. 020 7793 2600.