Lithium Monitoring And Toxicity

Lithium – mood stabilizer for bipolar disorder Compiled by Linda Stoneman April 2009

Lithium overview, lithium monitoring and protocol to help prevent toxicity

Lithium history • Lithium discovered by Swedish Chemist – Johan Arfredson in 1817. • Lithium is element no. 3 in the periodic table – a soft silvery metal. • Lithium is used as lithium salts including lithium carbonate, lithium citrate and lithium orotate. Li2CO3. Lithium Carbonate

Lithium uses and origins • Used as a mood stabilizer in the treatment of bipolar disorder. • Lithium must be used carefully as the dosages used for the treatment in humans is only slightly lower than toxic amounts. • Blood levels should be carefully monitored. Therapeutic levels range between 0.4 to 0.8 mmol/l. Toxic range usually 1.5 mmol/l, but may begin at 1.0.

Lithium uses and origins • Other forms of lithium include lithium chloride and lithium bromide, used for various purposes in manufacturing, engineering and bomb making! • The name lithium comes from the Greek name ‘LITHOS’ meaning stone. • It was discovered from a mineral

Lithium uses and origins • Lithium salts are chemical salts of lithium used primarily in the treatment of bipolar disorder as a mood stabilizer. • In the 2nd century it was noted that patients alternated between excitement and depression – possibly being the first documented cases of bipolar disorder.

Lithium uses and origins • Mood disorders were described by the Ancient Greeks and Romans as ‘mania’ and ‘melancholia’. In 1686 a connection was made of the two and was called ‘manico melancholias’. • Use of lithium salts came from springs and spas of Northern Italy. People bathed and drank the waters for soothing effects. The waters were later found to contain lithium salt.

Lithium uses and origins • In Modern times use of lithium salts to treat mania was first proposed by an Australian doctor in 1949. At this time other medicines also started to be used for other mental illnesses. • In the past, lithium has been used in popular fizzy drinks including Seven-Up, known as Lithiated Lemon and Lime Soda.

Lithium uses and origins • Seven-up contained lithium citrate until reformulated in 1950! • One brewery produced lithia beers – “West Bend”, but was forced to remove lithium in 1948. • An early version of Coca-Cola, obtained from pharmacies – Lithia Coke – a mixture of Coca-Cola Syrup and lithia waters.

Lithium uses and origins • The lithia waters were natural occurring mineral waters, with higher lithium amounts. • The amount of lithium in these drinks was hundreds of times less than in a minimum psychiatric dose. • Lithium comes in many forms and is toxic. • It should always be monitored by a doctor.

Common drug interactions • NSAID’s – Non-steroidal anti-inflamatory drugs – Ibuprofen. • Angiotensin converting enzyme inhibitors (ACE). • Diuretics (thiazides) • Rarer:- Antibiotics, antipsychotics, SSRI’s etc. (see BNF for further)

Common side effects of lithium • • • • • •

Abdominal pain Nausea Metallic taste in mouth (usually wears off) Fine tremor Thirst Weight gain and oedema

• Is the patient/doctor aware of the difference between side effects and signs of toxicity?

Signs of toxicity • • • • • • • • • • • • •

Lack of appetite Shaking and trembling Confusion/drowsiness Agitation and restlessness Slurred speech and/or blurred vision Nausea and vomiting Diarrhoea Abdominal pain Unsteadiness on the feet Muscle twitching Seizures Coma Death

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These symptoms can be very similar to that of an episode, and therefore difficult to differentiate. Agitation and restlessness are common in lithium toxicity, but a blood test should show if levels of lithium are toxic.

Hydration and toxicity • It is very important that the body stays fully hydrated when taking lithium. • If dehydration occurs the body will automatically ‘hang on to’ any fluid it has, but at the same time this means it will retain more lithium which is normally excreted by the kidneys in the urine. This is when toxicity occurs.

Blood Testing • Routine bloods monitoring should be carried out every 3/4 months. (Unless complicating factors or interactions then, monthly testing). • The doctor or nurse in primary care should be suitably trained in lithium monitoring. • The sample should be taken around 12 hours after the last dose of lithium taken, to give an accurate level. This is important. • It’s a good idea to keep a supply of signed bloods request forms at home for use as needed. Your GP should be able to supply you with these.

Questions to ask if worried about toxicity • Have you had an infection, cold or diarrhoea recently? • Have you got a fever or been sweating or loosing a lot of fluid? • Is it hot weather or have you been exercising a lot? • Have you been drinking a lot of coffee and/or alcohol? • Have you altered your salt in-take recently?

If at all worried seek advice • If you are worried about your lithium levels, and maybe showing some signs of toxicity, or indeed worried about your general mental/physical health, then seek advice early. • Toxicity can occur without apparent increase of serum level, so treating the patient and not the level is important. • See your GP or duty mental health doctor. • Get your blood tested as quickly as possible, and be reviewed by secondary care services or A&E the same day. • If in doubt and you or your carer are at all worried, go to your local A&E Department and tell them you think you may be lithium toxic.

If at all worried seek advice • Take advice from your doctor whether you should stop taking lithium – stopping lithium suddenly can cause a relapse in your condition, so this is best done supervised, and possibly with other medications being introduced. Lithium will be stopped if you are toxic. • Drink plenty of water if you suspect you are dehydrated or toxic. Do not drink alcohol or drinks with caffeine in.

Protocol • With the help of a health professional, draw up a protocol regarding lithium treatment, which will help in cases of emergency or if worried about toxicity. • Establish who will be responsible for monitoring ie. GP or mental health team, and decide how often testing should be done. • Lithium monitoring is ideally carried out using an agreed protocol. If carried out in primary care, monitoring should be done by a suitably trained person. • At each consult discuss any signs of toxicity.

Protocol • The GP should be informed of the target therapeutic serum level for each individual patient. • All test results should be communicated to the consultant psychiatrist. • Be aware of your current medications and doses. Stick to the same brand of lithium. • If you require any other medication, do you have any preferences or have you had problems in the past with certain drugs. • Have a note of useful telephone numbers ie. GP, Psychiatrist, Specialist Team and Helpline numbers.

Lithium Treatment Cards • Carry a lithium treatment card in your wallet or purse, so people can see you take lithium. These can be obtained from pharmacies or the drug manufacturers themselves. They help you keep track of regular blood tests and results.

References/reading • • • • • •

www.mind.org.uk www.bnf.org www.patient.co.uk www.bipolar.lives.com www.library.nhs.uk/mentalhealth www.nice.org.uk/Guidance/CG38 (Bipolar Disorder Management).

The End