lithium toxicity

lithium toxicity

1. LITHIUM TOXICITY PREPARED BY: Reejan Paudel (RN) MN 1 st year

2. LITHIUM Lithium is an element with atomic number 3 and atomic weight 7, which is the smallest alkaline ion. The element was discovered in 1817 by Arfuedson , since then, it has been used for treatment of gout and for salt replacement in cardiac disease, but its use was restricted due to fatal toxicity. It was rediscovered in 1949 by John Cade, for use in treatment of mania but its potential went unrecognized as it was discovered in Australia. Mogen Schou in 1957, had to rediscover it yet again before it became popular as a treatment of mania.

3. Pharmacokinetics: Lithium is very rapidly absorbed from the gastrointestinal tract. The peak serum levels occur between 30 min to 3 hours. 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. There is no metabolism of lithium in body and it is excreted almost entirely by the kidneys. Proximal reabsorption is influenced by the sodium balance, and depletion of sodium results in retention, causing higher blood levels of lithium.

4. Mechanism of action Lithium alters sodium metabolism within nerve and muscle cells and enhance (There are five known biogenic amines: dopamine, epinephrine, norepinephrine, histamine and serotonin) the reuptake of biogenic amines in the brain, lowering levels in the body and resulting in decreased hyperactivity. It may block development of sensitive dopamine receptors in the CNS of manic patient. Lithium has both anti-manic and antidepressant properties.

5. Indications Treatment of acute mania prophylaxis for bipolar and unipolar mood disorder Treatment of schizoaffective disorder Treatment of cyclothymia (mild form of bipolar disorder) Treatment of chronic alcoholism (in presence of significant depressive symptoms) and psychoactive use disorder (e.g. cocaine dependence) Impulsivity and aggression.

6. Other disorder: Premenstrual dysphoric disorder (severe form of PMS) bulimia nervosa episodes of binge drinking Trichotillomania: Trichotillomania, also known as trich , is when someone cannot resist the urge to pull out their hair. cluster headaches  

7. Dosage Lithium is available in the market in the form of the following preparations : lithium carbonate: 300 mg tablets ( Licab ); 400 mg sustained release tablets (e.g. Lithosun -SR) lithium citrate: 300 mg/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 600mg or 900mg of lithium to determine the pharmacokinetics.

8. BLOOD LITHIUM LEVEL: 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. Toxic lithium levels > 2.0 mEq /L

9. Side effects: Neurological : Tremors, motor hyperactivity, muscular weakness, cogwheel rigidity, seizure, neurotoxicity (delirium, abnormal involuntary movements, seizures, coma) Renal: Polydipsia (excessive thirst), polyuria, tubular enlargement, nephrotic syndrome Cardiovascular : T-Wave depression Gastrointestinal : nausea, vomiting, diarrhea, abdominal pain and metallic taste.

10. Endocrine : abnormal thyroid dysfunction, goiter and weight gain. Dermatological: acne form eruptions, papular eruptions, and exacerbation of psoriasis. Side effects during pregnancy and lactation: Teratogenic possibility, increased incidence of Ebstein’s anomaly (distortion and downward displacement of tricuspid valve in right ventricle) when taken in first trimester. Secreted in milk and can cause toxicity in infant. Lithium toxicity: toxicity occurs when serum lithium level >2.0 mEq /L

11. Pappular eruptions

12. Contraindications of lithium use Cardiac, renal, thyroid or neurological dysfunctions. Presence of body dystonia. (excessive involuntary muscle contractions leading to abnormal postures) During first trimester of pregnancy and lactation. Severe dehydration. Hypothyroidism. History of seizures.

13. LITHIUM TOXICITY Lithium toxicity is a potentially serious condition caused by having too much lithium in blood. Since Lithium’s primary medical use is as a disorder. According to the US Food and Drug Administration (FDA), in general the desirable level is 0.6 to 1.2 mEq /L. However, they point out, “Patients unusually sensitive to Lithium may exhibit toxic signs at serum levels below 1 mEq /L”. The higher the serum level, the likelier there will be both side effects and the appearance of toxic symptoms (also called lithium intoxication).  

14. TYPES OF LITHIUM TOXICITY Acute lithium toxicity: This most commonly occurs when someone who it’s taking lithium at all ingests it. This could occurs when a family member takes pills from the whole bottle, when a child gets into a parent’s medications, or in a suicide attempt. According to the researchers, acute toxicity can carry somewhat less medical risk and less severe symptoms that the other types, depending on amount taken.

15. Chronic Lithium Toxicity: The chronic form of lithium intoxication occurs in people who take lithium daily but the serum blood level has crept up into the toxic range. Possible causes are a dosage increase, dehydration, interactions with other medications, and problems with kidney function.

16. Causes Drugs related condition. Poisoning for suicide. Lithium toxicity is usually precipitated by dehydration, concurrent use of diuretics drugs such as HCT (Hydrochlorothiazide), usage of over the counter pain killers such as NSAIDS, rapid increase in the dose and renal impairment.

17. Sign and symptoms of lithium toxicity Ataxia : Ataxia means without coordination. Coarse tremor (hand) Nausea and vomiting Impaired concentration Nephrotoxicity : rapid deterioration in the kidney function due to toxic effect of medications and chemicals. Muscle weakness Convulsions

18. Muscle twitching Dysarthria Lethargy Confusion Coma Hyper- reflexia : Hyper- reflexia refers to hyperactive or repeating ( clonic ) reflexes.  Nystagmus  : a vision condition in which the eyes make repetitive, uncontrolled movements. 

19. Management of lithium toxicity Pre-hospital care: Stabilize life – threatening condition and initiate supportive therapy. Obtain intravenous access with isotonic (sodium chloride) solution. Monitor cardiac function to assess rhythm disturbances. Obtain all pill bottles available to the patient.

20. Emergency department care: Supportive therapy is the mainstay of treatment of lithium toxicity. Airway protection is crucial due to emesis and risk of aspiration. Seizures can be controlled with benzodiazepines, or phenobarbital.  

21. GI decontamination: Gastric lavage may be attempted if the patient presents within one hour of investigation. Lithium is a monovalent cat-ion that does not bind to charcoal; therefore, activated charcoal has no role. Whole- bowel irrigation with polyethylene glycol lavage can be effective in preventing absorption from extended-release lithium. Because of its similarities to potassium, the use of sodium polystyrene sulfonate has been proposed as a method of eliminating lithium.

22. Multiple-dose sodium polystyrene sulfonate  may be useful in lowering the serum lithium level of select patients with acute lithium overdoses but is not a substitute for hemodialysis in severely ill patients . Enhanced elimination: The mainstay of treatment is fluid therapy. The goal of saline administration is to restore glomerular filtration rate (GFR), normalize urine output, and enhance lithium clearance. Lithium is readily dialyzed because of water solubility, low volume of distribution, and lack of protein binding.

23. Hemodialysis is indicated for patient who have renal failure and are unable to eliminate lithium . It is also indicated in patient who cannot tolerate hydration such patients with congestive heart failure (CHF) or liver disease . Hemodialysis should be considered in patients who develop severe signs of neurotoxicity such as profound altered mental status and seizure. An absolute level of 4 mEq /L in acute toxicity and a level of 2.5 mEq /L in chronic toxicity in patients with symptoms should also be considered for hemodialysis .

24. Consultations Consult renal service personnel for hemodialysis in severe intoxication. Consult psychiatric service personnel for patient with intentional overdose. Consult the poison control center and a medical toxicologist regarding appropriate treatment.

25. REFERENCES   P.Subedi Durga , Mental health and psychiatric nursing, 4 th edition, Makalu publication 2018, page no. 370-375.   R Shreevani , A Guide to Mental Health & Psychiatric Nursing, 4 th edition, Jaypee Brothers Medical Publishers pvt. Ltd 2016, page no. 130 – 133.     Ahuja Neeraj , A Short textbook of Psychiatric, 7 th edition, Jaypee Brothers Medical Publishers pvt Ltd 2011, page no. 172-175 RETRIVED FROM: https://www.webmd.com/bipolar-disorder/what-to-know-about-lithium-toxicity https://www.healthline.com/health/lithium-toxicity