Lithium.pptx

Mental Health Nursing Unit V

1. Presented by: Mr. P. Vethadhas M.Sc (N), Assistant Professor, Dept.of Mental Health Nursing. Unit - v MOOD STABILIZING DRUGS

2. LITHIUM AND OTHER MOOD STABILIZING DRUGS Mood stabilizers are used for the treatment of bipolar affective disorders. Some commonly used mood stabilizers are: Lithium Carbamazepine Sodium valporate

3. LITHIUM

4. LITHIUM Lithium is an element with atomic number 3and atomic weight 7 . It was discovered by FJ Cade in 1949,and is a most effective and commonly used drug in the treatment of mania .

5. Indications Acute mania Prophylaxis for bipolar and unipolar mood disorder Schizoaffective disorder Cyclothymia Impulsivity and aggression

6. Indications Other disorders: Premenstrual dysphoric disorder Bulimia nervosa Borderline personality disorder Episodes of binge drinking Trichotillomania Cluster headaches

7. Pharmacokinetics Lithium is readily absorbed with peak plasma levels occurring 2-4 hours after a single oral dose of lithium carbonate. Lithium is distributed rapidly in liver and kidney and more slowly in muscle, brain and bone. Steady state levels are achieved in about 7 days. Elimination is predominantly via kidneys. Lithium is reabsorbed in the proximal tubules and is influenced by sodium balance. Depletion of sodium can precipitate lithium toxicity.

8. Mechanism of Action The probable mechanisms of action can be: It accelerates presynaptic re-uptake and destruction of catecholamines , like norepinephrine It inhibits the release of catecholamines at the synapse . It decreases postsynaptic serotonin receptor sensitivity. All these actions result in decreased catecholamine activity, thus ameliorating mania.

9. Dosage Lithium is available in the market in the form of the following preparations : Lithium carbonate: 300 mg tablets (e.g. Licab ); 400 mg sustained release tablets (e.g . Lithosun -SR ) Lithium citrate: 300mg/ 5ml liquid. The usual range of dose per day in acute mania is 900-2100 mg given in 2-3 divided doses. The treatment is started after serial lithium estimation is done after a loading dose of 600 mg or 900 mg of lithium to determine the pharmacokinetics.

10. Blood Lithium Levels Therapeutic levels = 0.8 - 1.2 mEq /L (for treatment of acute mania) Prophylactic levels = 0.6 - 1.2 mEq /L (for prevention of relapse in bipolar disorder) Toxiclithium levels > 2.0mEq/L

11. Side Effects

12. 1. Neurological: Tremors motor hyperactivity muscular weakness cogwheel rigidity seizures neurotoxicity (delirium, abnormal involuntary movements, seizures, coma).

13. 2. Renal: Polydipsia Polyuria Tubular enlargement Nephrotic syndrome

14. 3. Cardiovascular: T -wave depression.

15. 4. Gastrointestinal: Nausea Vomiting Diarrhea Abdominal pain and metallic taste.

16. 5. Endocrine: Abnormal thyroid function Goiter and Weight gain.

17. 6. Dermatological: Acneiform eruptions, Papular eruptions and Exacerbation of psoriasis.

18. 7 . Side-effects during pregnancy and lactation: Teratogenic possibility, I ncreased incidence of Ebstein's anomaly (distortion and downward displacement of tricuspid value in right ventricle)when taken in firsttrimester . Secreted in milk and can cause toxicity in infant.

19. 8 . L ithium toxicity : Toxicity occurs when serum lithium level >2.0 mEq /L )

20. Signs and symptoms of lithium toxicity Ataxia Coarse tremor (hand) Nausea and vomiting Impaired memory Impaired concentration Nephrotoxicity Muscle weakness

21. Signs and symptoms of lithium toxicity Convulsions Muscle twitching Dysarthria Lethargy Confusion Coma Hyperreflexia Nystagmus

22. Management of Lithium Toxicity Discontinue the drug immediately. For significant short-term ingestions, residual gastric content should be removed by induction of emesis, gastric lavage and adsorption with activated charcoal. If possible instruct the patient to ingest fluids. Assess serum lithium levels, serum electrolytes , renal functions , ECG as soon as possible .

23. Management of Lithium Toxicity Maintenance of fluid and electrolyte balance. In a patient with serious manifestations of lithium toxicity, hemodialysis should be initiated.

24. Contraindications of Lithium Use Cardiac, renal, thyroid or neurological dysfunctions Presence of blood dyscrasias During first trimester of pregnancy and lactation Severe dehydration Hypothyroidism History of seizures

25. Nurse's Responsibilities for a Patient Receiving Lithium The pre-lithium work up: A complete physical history, ECG , blood studies (TC,DC, FBS,BUN, creatinine , electrolytes) urine examination (routine and microscopic)must be carried out. It is important to assess renal function as renal side effects are common and the drug can be dangerous in an individual with compromised kidney function. Thyroid functions should also be assessed, as the drug is known to depress the thyroid gland.

26. To achieve therapeutic effect and prevent lithium toxicity, the following precautions should betaken: Lithium must be taken on a regular basis, preferably at the same time daily ( for example , a client taking lithium on TID schedule , who forgets a dose should wait until the next scheduled time to take lithium and not take twice the amount at one time , because lithium toxicity can occur). When lithium therapy is initiated, mild side effects such as fine hand tremors, increased thirst and urination, nausea, anorexia etc may develop. Most of them are transient and do not represent lithium toxicity.

27. cont…, Serious side-effects of lithium that necessitate its discontinuance include vomiting, extreme hand tremors, sedation , muscle weakness and vertigo. The psychiatrist should be notified immediately if any of these effects occur. Since polyuria can lead to dehydration with the risk of lithium intoxication, patients should be advised to drink enough water to compensate for the fluid loss.

28. cont…, Various situations may require an adjustment in the amount of lithium administered to a client , such as the addition of a new medicine to the client's drug regimen, a new diet or an illness with fever or excessive sweating. In this connection , people involved in heavy outdoor labor are prone to excessive sodium loss through sweating. They must be advised to consume large quantities of water with salt, to prevent lithium toxicity due to decreased sodium levels. If severe vomiting or gastroenteritis develops, the patient should be told to report immediately to the doctor. These are the conditions that have a high potential for causing lithium toxicity by lowering serum sodium levels..

29. cont…, Frequent serum lithium level evaluation is important. Blood for determination of lithium levels should be drawn in the morning approximately 12-14 hours after the last dose was taken. The patient should be told about the importance of regular followup . In every six months, blood sample should be taken for estimation of electrolytes, urea, creatinine , a full blood count, and thyroid function test.

30. Thank you