ADVERSE EFFECTS Metabolic alkalosis and/or hypokalaemia may ensue as a result of prolonged use or over correction of the bicarbonate deficit, especially in patients with impaired renal function. (see OVERDOSAGE ) Metabolic alkalosis may be accompanied by compensatory hyperventilation, paradoxical acidosis of the cerebrospinal fluid, severe hypokalaemia, hyperirritability or tetany. Hypernatraemia has been reported with sodium bicarbonate use, especially in patients with renal disease. Hyperosmolality has also been associated with sodium bicarbonate use. Accidental extravasation of intravenous hypertonic solutions of sodium bicarbonate has been reported to cause chemical cellulitis, with tissue necrosis, tissue calcification, ulceration or sloughing at the site of infiltration. Prompt elevation of the part, warmth and local injection of lignocaine or hyaluronidase are recommended to prevent sloughing of extravasated intravenous infusions. Hyperirritability or tetany may occur, caused by rapid shifts of free ionised calcium or due to serum protein alterations arising from the pH changes. Cerebral oedema has occurred with sodium bicarbonate use and a possibility of intracranial haemorrhage exists. Hypercapnia has occurred in patients receiving sodium bicarbonate and with fixed ventilation.