Side effects at therapeutic concentrations

Common side effects include hand tremor, muscular weakness, nausea, polydipsia, polyuria, weight gain and oedema.

These are not usually dangerous, but may indicate the beginning of the toxic syndrome.

• tremor is very common.
• thyroid enlargement, hypothyroidism, ECG changes and EEG changes, nephrogenic diabetes-insipidus and depletion of calcium from bone may also take place. Long-term lithium treatment is associated with persistent hyperparathyroidism and hypercalcaemia (1).
• patient may complain of a metallic taste in the mouth during lithium treatment.
• skin rashes may occur.

Reference:

1. Drug and Therapeutics Bulletin 1999; 37 (3): 22-24.