<prompt> Long term use of lithium causes -HypopituitarismDiabetes mellitusHypothyroidismHyperthyroidism  <response>: Ans. is c i.e., Hypothyroidism o Lithium can cause hypokalemia.Side effects of lithium1 Neurological: - Tremor is the commonest side effect of lithium. Other CNS side effects are giddiness, ataxia, motor incordination, hyperreflexia, mental confusion, nystagmus.2 Renal: - Nephrogenic diabetes insipidus with polyuria polydipsia. Amiloride is the DOC for Lithium induced nephrogenic DI.3 Cardiovascular: - Effects are similar to hypokalemia which causes arrhythmia. Most common ECG change is T wave depression.4 Endocrine: - Goitre, hypothyroidism.5 GIT: - Nausea, vomiting, diarrhoea, metallic test, abdominal pain.6 Dermatological: - Acneiform eruptions, papular eruption, exacerbation of psoriasis.7 Teratogenicity: - Ebsteins anomaly in fetus. 