PROCEDURE REF NO SABP/EXECUTIVE BOARD/0017 NAME OF PROCEDURE: REASON FOR THE PROCEDURE: WHAT THE PROCEDURE WILL ACHIEVE: WHO NEEDS TO KNOW ABOUT IT: DATE APPROVED: VERSION NUMBER: APPROVING COMMITTEE: Medicines Procedure: Lithium Therapy: Prescribing and Monitoring The Patient Safety Alert NPSA 2009/PSA005: Safer lithium therapy 1. Reduce risk 2. Facilitate confident prescribing, monitoring, administration and dispensing of lithium 3. Improve awareness All staff involved in the prescribing, dispensing or administering of lithium November 2014 2 Executive Board DATE OF IMPLEMENTATION: November 2014 DATE OF FORMAL REVIEW: November 2017 AUTHOR/REVIEWER: DIRECTORATE RESPONSIBLE: DISTRIBUTION: Medicines Management Committee All staff involved in the prescribing, dispensing or administering of lithium Page 1 of 16
POLICY, PROCEDURE AND GUIDELINE DEVELOPMENT PROCEDURE VERSION CONTROL SHEET Version Date Author Status Comment 0.1 March 2011 Fiona Lockwood 0.2 September 11 Simon Whitfield 1.1 October 14 Fiona Lockwood draft Draft ready for Oct 11 PAG Draft ready for Nov 14 PAG New procedure sent out for consultation Reviewed but no changes necessary Page 2 of 16
Summary of Changes since Version 1.0 (Include version control number here) Page /Paragraph/ Appendix Number (select the appropriate action) Original / New / Amendment / Deleted Statement (select the appropriate action) No changes since consultation Page 3 of 16
PROCEDURE FOR THE PRESCRIBING AND MONITORING OF LITHIUM THERAPY 1.0 INTRODUCTION In December 2009 the NPSA issued a Patient Safety Alert on safer lithium therapy. The alert was in response to reports of harm caused to individuals, including fatalities, involving lithium therapy. This procedure sets out guidelines to ensure that this Patient Safety Alert is complied with when lithium is prescribed, monitored, administered and dispensed. 2.0 RELATED POLICY The Medicines Policy. 3.0 ON ADMISSION 3.1 INITIATION (ALSO APPLIES IN COMMUNITY SETTING see the Trust Lithium Amber* information sheet for prescribing in the community) 3.1.1 Ensure the following baseline data has been established before commencement of treatment: ECG if there are risk factors for, or existing cardiovascular disease Weight and height Urea and Electrolytes Serum creatinine Thyroid Function Tests; specifically TSH. If TSH abnormal, test T3 and T4 Full blood count if clinically indicated 3.1.2 Plasma level of lithium must be taken 12 hours post dose; checked 1 week after initiation and 1 week after every dose change and until the levels are stable. (See Appendix 1) 3.1.3 The starting dose is normally 400mg (200mg in the elderly). Page 4 of 16
3.1.4 Doses should be adjusted to achieve a plasma lithium concentration between 0.4 and 1.0mmol/L in people being prescribed it for the first time. The lower end of the range is usually the target for maintenance therapy and treatment of elderly individuals 3. 3.1.5 If an individual has just been initiated on lithium, the pharmacist should check that the baseline monitoring tests have been carried out (see Appendix 1). If not, the prescriber should be informed of the need for monitoring. 3.2 ADMITTED ON LITHIUM 3.2.1 The admitting doctor must: Read the individual s notes and previous prescription, check individual s documentation (either a record book and alert card or a monitoring booklet) and identify any special instructions. Review the results of all relevant investigations (including blood test results) and identify the indication for the lithium therapy. 2 At the earliest opportunity contact the individual s GP for advice, if the individual is admitted without an up-to-date documentation. 2 Ensure that the individual fully understands their lithium treatment and monitoring requirements and if not, provide a clear explanation. Ensure the correct brand of lithium is prescribed as different preparations may vary in bioavailability; care should be taken when changing brands or formulations and should be regarded as initiation of new treatment. 3.2.2 Pharmacy team responsibilities: The medicines management technician should alert the ward pharmacist to any individual prescribed lithium and any subsequent additional items prescribed. The medicines management technician or ward pharmacist should undertake a full drug history on admission and record the brand of lithium on the drug chart in the additional information box and in the individual s notes. N.B. this information may be obtained from the individual s lithium record book. If individuals are admitted on lithium they should be asked to produce their lithium record book by a pharmacist or technician. This is to ensure that there is no ambiguity regarding dosage and formulation and that monitoring has occurred. A supply can be made from the local Pharmacy if required. Page 5 of 16
Any patient s own lithium brought into hospital should be checked in accordance with the Patient s Own Drugs Procedure. The pharmacist should review the in-patient medicine chart before any supply is made and ensure that the prescription is complete and accurate, the brand stated and that monitoring is in place. The ward pharmacist should check if the routine monitoring tests have been carried out (see Appendix 2). If these results are not accessible, pharmacists should inform medical staff to request the relevant tests. As a principle, therapy should not be withheld but the prescriber informed of the need for monitoring. The pharmacist should check for any drug interactions. If the individual is prescribed other potentially interacting medicines e.g. NSAIDs, diuretics or if an interacting medicine is discontinued, the prescriber should be contacted to ensure they are aware of the interaction and that arrangements have been made for additional tests to be carried out if necessary. 3.3 CONTINUING TREATMENT ON ADMISSION 3.3.1 Where necessary, the care team must update the monitoring results in the individual s record book 3.3.2 Nurses responsibilities: Nurses need to be aware of common side effects of lithium listed below and report to the ward doctor if they have concerns. Gastro-intestinal disturbances Fine tremor Renal impairment (particularly impaired urinary concentration and polyuria) Polydipsia Leucocytosis Weight gain Oedema (may respond to dose reduction) Nurses need to monitor the individual and report to the ward doctor if symptoms of lithium toxicity appear. (See Appendix 3) Nurses must also: Inform anyone who is involved in the individual s care, that the individual is taking lithium. Page 6 of 16
Advise the individual to avoid dietary changes which reduce or increase sodium intake. Advise the individual to avoid the use of over the counter analgesics such as ibuprofen. 1 3.3.3Prescribers responsibilities: Record lithium levels on the drug chart with the date of the test and enter in the notes. Be aware of any significant interacting drugs and other risk factors for lithium toxicity. (See Appendix 3) Undertake more frequent blood tests and lithium levels if there are signs of clinical deterioration, abnormal results, and symptoms suggesting abnormal renal or thyroid function such as unexplained fatigue. 1 Repeat lithium levels if they initiate or discontinue any interacting drugs. (Check at 7 day intervals until two similar results are obtained at the same dose). 1 Repeat lithium levels if they increase or decrease lithium dose. (Check at 7 day intervals until two similar results are obtained at the same dose). Be aware that toxicity occurs when blood lithium concentration is greater than 1.5mmol/L. (Usual therapeutic range is between 0.4 1.0mmol/L for people being prescribed it for the first time.) For people who have relapsed previously while taking lithium or who have sub-threshold symptoms with functioning impairment while on lithium target level is normally between 0.8 1.0mmol/L 1 Monitor for symptoms of neurotoxicity, including paraesthesia, ataxia, tremor and cognitive impairment, which can occur at therapeutic levels. Consider stopping lithium for up to 7 days if individuals become acutely and severely ill with any metabolic or respiratory disturbance. 1 STOP lithium immediately, if any of the symptoms of toxicity occur. (See appendix 3). Plasma lithium levels should be urgently checked and the individual rehydrated with an increased sodium intake. Levels of 2mmol/L or more require urgent treatment as per guidance in the BNF and Maudsley Prescribing Guidelines. 3, 4 Page 7 of 16
Exclude pregnancy (and test if appropriate) in women of child bearing potential and advise these individuals to use suitable contraception. (If a individual becomes pregnant, refer for specialist advice). 3.3.4 Pharmacy team responsibilities: Check that blood tests and lithium levels have been obtained at the appropriate times and where not, arrange for them to be taken as necessary. Check that the latest lithium level (and date) is written on the drug chart. If it is not, check the clinical notes and make the appropriate drug chart entry. Ask individuals who have been admitted on lithium if they have a lithium record book. Where possible, check that this is correctly completed. Review the drug chart before any supply is made and ensure that the prescription is complete, the brand stated and that monitoring is in place. Before endorsing the chart all prescriptions must be checked for drug interactions, which must be reported back to the prescriber as necessary. Ensure the importance of administering lithium in the evening (for tablets) is clear to the medical and nursing team. Pharmacists should not withhold lithium therapy. Where it is not possible to assess monitoring they should communicate to prescribers that lithium medication has been provided without blood test data being available and that this should be investigated as soon as possible. 2 4.0 ON DISCHARGE 4.1 Prescribers responsibilities: Ensure that the primary care team is sent information concerning the clinical indication of use, intended duration of therapy, current prescription (including product brand name), and recent laboratory test results. Ensure that the record book or monitoring booklet is FULLY and appropriately completed (with individual s details, service providers details and current lithium therapy to track lithium blood levels and relevant clinical tests) and that it is returned to individual/carer, with the next appointment date recorded. 2 Page 8 of 16
Use the Trust Lithium Amber* information sheet to liaise with the individual s GP for prescribing and monitoring lithium and also checking adverse effects. Ensure individuals receive regular measurement of serum-lithium concentration (every 3 months on stabilised regimen), and also renal function and thyroid function tests every 6 months on stabilised regimens, or more often if there is evidence of impaired renal function. 1 4.2 Nursing Team responsibilities: 4.2.1 Ensure the following are discussed with the individual: The dose they should be taking on discharge and the frequency. The date of their next appointment for a blood test. The importance of their individual-held records, (record book, alert card and patient information booklet). The need to take lithium at the same time each day (usually in evening) 4.3 Pharmacy Team responsibilities: 4.3.1 For newly initiated individuals, pharmacists should ensure that the individual has received a lithium record book and that they have been advised to produce this record book each time they have contact with a healthcare professional. 4.3.2 Pharmacists should ensure that the individual has been counselled on the frequency of administration, strength of tablets/liquid, dietary advice, signs and symptoms of toxicity etc. as well as common interactions e.g. NSAIDs (see Appendices 3 & 4) 4.3.3 The record book should be updated on discharge if any changes have occurred to the lithium dose whilst an in-patient; this should be checked by a pharmacist. The book should state the dose, brand and a record of blood tests. This should be completed by medical staff but may be completed by a pharmacist. Ask the individual if they have any questions about their lithium or if they have noticed any side effects. If side effects are experienced, the pharmacist should discuss them with the prescriber as they could be signs of toxicity or intolerance. Ensure the individual is aware of the potential of lithium to interact with other medications. (See Appendix 4) Page 9 of 16
Remind the individual to report any unusual signs and symptoms to their G.P: e.g. sore throat, bruising, mouth ulcers, nausea, vomiting, dark urine and shortness of breath. Give the individual a lithium information booklet if they have not already received one along with an alert card. Ensure they are adequately counselled, particularly if their ability to read the booklet is in question. Ensure the monitoring record book is returned to individual with all sections filled appropriately. This should include the individual s details, service provider s details, current lithium therapy and the date for next appointment for blood monitoring. 2 Advise the individual to monitor and report any signs or symptoms suggestive of hypothyroidism such as lethargy and feeling cold. Advise the individual to maintain a constant fluid and salt intake and avoid large dietary changes. Page 10 of 16
REFERENCES 1. National Institute for Clinical Excellence (NICE). Bipolar Disorder: the management of bipolar disorder in adults, children and adolescents, in primary and secondary care. Clinical Guideline 38, 2006. www.nice.org.uk 2. National Patient Safety Agency (NPSA) Alerts Summary Lithium Dec 2009 3. BNF No 60 September 2010 4. Maudsley Prescribing Guidelines 9 th edition, 2007, pg149 5. Dorset Healthcare NHS Foundation Trust. Ref No CP-170-08, lithium prescribing & Monitoring Guidelines 6. Stockley s Drug Interaction 7 th edition Chapter 29, Pg. 845-861 7. Guidelines for the Prescribing and Monitoring of Lithium Therapy: Sussex Partnership NHS Foundation Trust Page 11 of 16
Appendix 1 BASELINE MONITORING Parameter Notes Initial assessment of suitability for lithium treatment Renal Function Thyroid Function Full Blood Count ECG Specifically urea, electrolytes and serum creatinine to calculate Egfr Specifically TSH; if TSH abnormal, test T3 and T4 levels Only if clinically indicated Before initiation if there are risk factors for or existing cardiovascular disease Weight and Height Serum Levels of Lithium Level must be taken 12 hours post dose, checked 1 week after starting and 1 week after every dose change, and until the levels are stable Page 12 of 16
Appendix 2 ROUTINE MONITORING Parameter Frequency Notes Renal Function Thyroid Function Full Blood Count Weight and Height Serum Levels of Lithium Every 6 months; more often if there is evidence of deterioration or the individual starts taking drugs such as ACE inhibitors, diuretics or NSAIDs Every 6 months; more often if evidence of deterioration Only if clinically indicated If individual continues to gain weight Every 3 months or if dose change or some other indication or evidence of deterioration, then 1 week after every dose change, and until the levels are stable, then every 3 months Specifically urea, electrolytes and serum creatinine to calculate egfr Specifically TSH; if TSH abnormal, test T3 and T4 levels Page 13 of 16
Appendix 3: Lithium Toxicity. Symptoms of lithium toxicity 1) Severe nausea 2) Anorexia 3) Vomiting or diarrhea 4) Muscle weakness 5) Coarse tremor 6) Ataxia 7) Myoclonus (unexplained involuntary jerks) 8) Blurred vision 9) Drowsiness or increased disorientation 10) Confusion 11) Arrhythmias 12) Renal failure 13) Circulatory failure 14) Hypothyroidism 15) Hypokalaemia 16) Raised anti-diuretic hormone concentration 17) Coma 18) Occasionally death When lithium blood levels are above 2mmol/l and severe symptoms are present, osmotic diuresis or forced alkaline diuresis should be initiated. (Note: concurrent use of diuretics, particularly thiazides, should be avoided). 3 Page 14 of 16
Appendix 4: Information for Clinicians on Managing Lithium Drug Interactions DRUG ACE inhibitors e.g. enalapril, Angiotensin-II antagonists e.g. losartan Analgesics (NSAIDs) e.g. diclofenac, ibuprofen, aspirin Anti-arrhythmics e.g. amiodarone Antidepressants eg. SSRIs, Tricyclics, venlafaxine Diuretics (thaizides, potassiumsparing and loop diuretics) Methyldopa Antiepileptics e.g. carbamazepine, phenytoin, topiramate Antacids e.g. Sodium bicarbonate Metronidazole Calcium channel blockers Theophylline Parasympathomimetics Acetazolamide Antipsychotics Muscle Relaxants Lithium Interaction Alert 3, 6 INTERACTION Excretion reduced, Increased plasma concentration. May cause toxicity. Monitor closely for signs of lithium toxicity, and consider taking lithium levels. Be alert for the need to reduce the lithium dose (possibly by one-third to half). Excretion of lithium reduced. Increased risk of toxicity. Avoid concomitant use. Paracetamol based painkillers are safer to use with lithium. Risk of ventricular arrhythmias. Avoid concomitant use. Increased serotogenic effects seen and an increased risk of CNS effects as well as risk of lithium toxicity reported. All can increase lithium toxicity without affecting lithium levels. Excretion reduced. Increased plasma concentration and risk of toxicity. Loop diuretics are safer than thaizides. Neurotoxicity may occur without increasing plasma concentration of lithium. Avoid concurrent use whenever possible. Neurotoxicity may occur without increased lithium plasma concentrations. Moderate interaction Excretion increased. Reduced plasma concentration. Increased risk of lithium toxicity Neurotoxicity may occur with diltiazem or verapamil without increasing the plasma concentration of lithium. Increased excretion of lithium. Reduced plasma lithium concentration. Depressive and manic relapse may occur if the dosage of lithium is not raised when theophylline is given. Lithium levels should be monitored if theophylline (or aminophylline) is stopped, started or altered. Lithium antagonises the effects of neostigmine and pyridostigmine. Excretion of lithium is reduced. Increased risk of extrapyramidal side effects and possible neurotoxicity. Sertindole increases risk of ventricular arrhythmias - avoid concomitant use. Lithium enhances the effect of muscle relaxants. Hyperkinesis caused by lithium is aggravated by baclofen. Page 15 of 16
DRUG DISEASE INTERACTION (Other risk factors) If renal impairment exists, avoid use of lithium (if possible) or reduce dose and closely monitor serum-lithium concentration. 3 Cardiac disease and conditions with sodium imbalance such as Addison s disease will require dose reduction or discontinuation. Similarly, in severe diarrhoea and/or vomiting and in concurrent infection, (especially if sweating profusely). 3 Psoriasis: risk of exacerbation. 3 Page 16 of 16