Week 8- Lithium

Question 1

what is lithium used for?

Answer 1

 Prophylaxis against bipolar disorders
 In the management of acute manic or
hypomanic episodes (must have previously
responded to Lithium and symptoms not
severe)
 Recurrent depression
 Control of aggressive behaviour or intentional
self harm

Question 2

what does do and know for doing?

Answer 2

-Gold Standard for
relapse Prevention, increases time between episodes
-rarely used in mania and has a delayed onset of time of around 5-7 days ad needs higher levels

Question 3

what is the mechanism of action of lithium? what state does it come in?

Answer 3

-not fully known
-lithium modifies the
production and turnover of certain neurotransmitters, particularly serotonin, and it
may also block dopamine receptors.
- is an alkali metal (similar to salt)
available for medical use as lithium carbonate
or lithium citrate.

Question 4

what preparations dos lithium come in? whats important when prescribing lithium?

Answer 4

 Preparations vary widely in
bioavailability.
 Ensure patient is maintained on
same brand.
 At NSFT we stock Priadel M/R Tablets 200mg and 400mg
(Lithium Carbonate) and Priadel Liquid 520mg/5ml (Lithium
Citrate).
 Dose conversion between Priadel M/R tablets and Priadel Liquid
NOT comparable.
 5ML of Lithium Citrate liquid 520mg/5ml is approximately equal to
ONE Lithium Carbonate 200mg M/R tablets.
 Other brands include Camcolit,Liskonum and Li-Liquid.

Question 5

what are some contraindications of lithium therapy?

Answer 5

 Hypersensitivity to lithium or to any of the excipients.
 Cardiac disease.
 Cardiac insufficiency.
 Severe renal impairment.
 Untreated hypothyroidism.
 Breast-feeding
 Patients with low body sodium levels, e.g. dehydratedpatients or those on low sodium diets.
 Addison’s disease.
 Brugada syndrome- hereditary disease of the cardiac
sodium channel

Question 6

what are some cautions for lithium therapy?

Answer 6

 Pregnancy- should AVOID using unless exceptional
circumstances, esp first trimester
 Renal Impairment
 ECT and other medication that can
decrease epileptic Threshold
 QT interval prolongation and medication
that increases QT

Question 7

what are the physical monitoring before initial treatment of lithium therapy?

Answer 7

 E.C.G – can increase QT interval.
 Renal Function (Egfr)- Lithium is excreted via
Kidneys.
 Thyroid function- Hypothyroidism can be
mistake for depression.
 Weight/BMI, Ca, U&E’s and FBC

Question 8

what are the physical monitoring during initial treatment of lithium therapy?

Answer 8

 Lithium has a narrow therapeutic window
 Regular blood tests required to ensure therapeutic
dose maintained and to monitor for toxicity.
 Plasma levels must be taken weekly until stable
concentrations maintained for 4 weeks.
 Plasma levels should 4-7days after each dose change
until stable.
 NICE- take plasma levels every 3 months for 1st year (
at NSFT we continue this) then 6monthly unless at risk
 Blood test should be taken 12 hours post
dose.
 Range should be 0.4 to 1 mmol/L ( higher end
in Mania).
 Lower range in elderly.
 Renal Function (Egfr) and Thyroid
function(TSH and T4)monitored every 6
months.
 Weight/BMI, Ca, U&E’s

Question 9

what dosage of lithium is used ?

Answer 9

 Dosage must be individualised
depending on serum lithium levels and
clinical response.
 Usual starting dose 200mg in elderly and
400mg in Adults.
 Usual dose range 400mg-1.2g Daily
 Reduced dose in renal impairment (avoid
if possible) and patients <50KG.

Question 10

what are some of the side effects

Answer 10

 Upset stomach-particularly at start of
treatment.
 FINE tremor of the hands.
 Metallic taste in the mouth.
 Swelling of ankles- dose reduction.
 Increase thirst and urine output- renal
impairment.
 Weight gain- up to 27KG.

Question 11

what is lithium toxicity ?

Answer 11

 Blood concentrations over 1.5mmol/L
(over dosage) may be fatal and have a
toxic effect.
 Blood concentrations over 2mmol/L
(severe over dosage) requires urgent
medical attention.
-always check patients compliance

Question 12

what are some signs and symptoms of lithium toxicity?

Answer 12

 SEVERE hand tremor
 Stomach ache with nausea and diarrhoea
 Muscle Weakness
 Unsteady on feet
 Slurring of words
 Blurred Vision
 Confusion
 Unusually Sleepy
 Muscle Twitches

Question 13

what are some signs and symptoms of lithium toxicity?

Answer 13

 Convulsions
 Coma
 Renal and circulatory failure
 Hyperreflexia- overactive reflexes
 Toxic Psychoses

Question 14

what are some drug interactions that can increase litium?

Answer 14

 ACE inhibitors-e.g Ramipril
 Angiotensin II receptor antagonist- e.g Candesartan NSAIDS- AVOID concomitant use
 cyclo-oxygenase (COX) 2 inhibitors- e.g Ketorolac,
AVOID
 Metronidazole
 SSRI’s
 Diuretics and Aldosterone anatagonists –e.g
Bumetanide/Furosemide(least
risk),Bendroflumethiazide and Spironolactone

Question 15

what are some drug interactions that decrease lithium levels?

Answer 15

 Sodium bicarbonate containing products

 Caffeine

Question 16

what are some other interactions that occur with lithium?

Answer 16

Other Interactions
 Ventricular Arrhythmia can be caused by
concomitant use with Amiodarone-AVOID
 Increased risk of neurotoxicity with Methyldopa
and some antipsychotics e.g Clozapine

Question 17

what are other risks that increase lithium levels? what should patients be monitored for?

Answer 17

Sodium depletion increases Lithium concentration
due to competitive re absorption at the renal
level
 Dehydration- Ensure adequate fluid
intake
 Changes in Salt levels in diet
 Infection
 Vomiting and Diarrhoea

Question 18

what are some counselling points for taking lithium?

Answer 18

• Once daily at NIGHT to minimise renal damage
• Effectiveness takes 6/12 to fully establish
• Duration of treatment 2-3 years minimum
• Take it regularly – erratic compliance is dangerous
• Lithium must not be stopped rapidly
• Should be stopped stepwise over at least 4 weeks, preferably longer e.g. 6 months
• Make sure plasma level monitoring is regular (3 months) to reduce renal damage potential
• Keep up fluid intake – “don’t ignore feelings of thirst”, particularly after sweating, hot climates• Seek medical attention if develop diarrhoea or vomiting
• Lithium may lose a little efficacy if stopped and restarted so don’t risk it
• Warn patients not to take OTC NSAIDs

Question 19

what does NPSA recommend for all lithium therapy patients? what does it include, used for?

Answer 19

 NPSA advises that all
patients initiated and
maintained on lithium
must be issued a
Lithium Therapy
Booklet.
 Contains Information
booklet, record book and
Lithium Alert card
 Alert Card-contains brand and dose of
Lithium, NHS number and emergency
details.
 Record book- includes lithium blood
levels, Thyroid and renal function and
weight chart- must be presented when
obtaining Lithium from community
Pharmacy.
 Information Pack-Advice for patients