Lithium
- Monovalent cation and get rapidly and completely absorbed after oral administration
- t1/2 – 1.3 days but increased to 2.4 days after continued TT for more than 1 year
- Not metabolized in body and excreted unchanged in kidney
Indications:
- Acute Manic Episode
- Schizoaffective Ds
- Bipolar Depression
- OCD
- Gout
- Epilepsy
- Maintenance Therapy
- Cluster migraine
- Ulcerative Colitis
Narrow therapeutic index Acute Mania [1.0-1.5 meq/dL] and maintenance [0.6-1.2 meq/dL]
Neurological Side Effect Postural tremors [T/T Propranolol], Lack of spontaneity, decreased memory, ↑ ICT and peripheral neuropathy
Endocrine – Hypothyroidism [Rarely hyperthyroidism]
Renal – Polyuria may lead to diabetes insipidus, Rarely Nephrotic Syndrome, RTA & Intestinal fibrosis
Others – Acne, Psoriasis, Nausea, vomiting, diarrhea, weight gain, Benign T wave change
Lithium Toxicity:
- Risk Factors – Renal impairment, dehydration and Low sodium diet
- Earliest symptoms – GI Symptoms [Abdominal pain, vomiting] followed by neurological symptoms like coarse tremors, ataxia and dysarthria.
- Late Symptoms – Impairment of consciousness, muscular fasciculation’s, ↑ DTR, Convulsions, Circulatory Failure
- Management – Stop Lithium. Correct Dehydration, Polyethylene Glycol Gastric lavage & hemodialysis
