Lithium Pharmacology - Side Effects

Side Effects

The most common side effects are an overall dazed feeling and a fine tremor of hands. These side effects are generally present during the length of the treatment, but can sometimes disappear in certain patients. Other common side effects, such as nausea and headache, can be generally remedied by a higher intake of water. Lithium unbalances electrolytes; to counteract this, increased water intake is suggested.

Lithium is known to be responsible for significant amounts of weight gain. Because lithium competes with the receptors for the antidiuretic hormone in the kidney, it increases water output into the urine, a condition called nephrogenic diabetes insipidus. Clearance of lithium by the kidneys is usually successful with certain diuretic medications, including amiloride and triamterene. It increases the appetite and thirst ("polydypsia") and reduces the activity of thyroid hormone (hypothyroidism). The latter can be corrected by treatment with thyroxine. Lithium is also believed to permanently affect renal function, although this does not appear to be common.

Lithium is a well-known cause of downbeat nystagmus, which may be permanent or require several months of abstinence for improvement.

Most side effects of lithium are dose-dependent. The lowest effective dose is used to limit the risk of side effects.