Avoidance of lithium intoxication: advice based on knowledge about the renal lithium clearance under various circumstances.

To avoid lithium intoxications, clinicians should counteract conditions under which lithium clearance changes. If that is not possible, the lithium dosage should be adjusted to the lithium clearance. Lithium clearance is usually 20-30 per cent of the glomerular filtration rate and varies with it, for example during pregnancy and kidney disease. Lithium clearance may also change independently of the glomerular filtration rate. It decreases for example during dehydration (water deficiency) and low sodium intake, pathological conditions with edema formation, treatment with diuretics, anti-hypertensive drugs, or non-steroid anti-inflammatory drugs. It increases during treatment with some vasodilating drugs. Precautionary measures against lithium intoxication are suggested for each of these situations.