Which statement regarding potential untoward effects of lithium therapy is NOT true?

Which statement regarding potential untoward effects of lithium therapy is NOT true?

• A. Long-term administration may be associated with nephrogenic diabetes insipidus.
• B. Administration of succinylcholine to patients treated with lithium may result in hyperkalemia.
• C. Long-term therapy may be associated with hypothyroidism.
• D. Duration of action of pancuronium may be prolonged.

Answer: (B)

Lithium’s untoward effects mainly include renal and thyroid system involvement and potential effects on neuromuscular blockade. Long-term lithium can impair the kidney’s ability to concentrate urine, leading to nephrogenic diabetes insipidus. It can also affect the thyroid, with hypothyroidism occurring in some patients on chronic therapy. In the operating room, lithium can influence how long certain neuromuscular blockers last; specifically, the action of nondepolarizing agents like pancuronium can be prolonged because lithium can alter renal drug clearance and neuromuscular transmission. The statement about using succinylcholine in patients on lithium causing hyperkalemia is not a recognized risk unique to lithium therapy. Hyperkalemia with succinylcholine occurs in other conditions that upregulate extrajunctional acetylcholine receptors (such as burns, denervation injuries, or severe neuromuscular diseases), not as a direct consequence of lithium treatment. Hence, this option is not true.

Lithium’s untoward effects mainly include renal and thyroid system involvement and potential effects on neuromuscular blockade. Long-term lithium can impair the kidney’s ability to concentrate urine, leading to nephrogenic diabetes insipidus. It can also affect the thyroid, with hypothyroidism occurring in some patients on chronic therapy. In the operating room, lithium can influence how long certain neuromuscular blockers last; specifically, the action of nondepolarizing agents like pancuronium can be prolonged because lithium can alter renal drug clearance and neuromuscular transmission.

The statement about using succinylcholine in patients on lithium causing hyperkalemia is not a recognized risk unique to lithium therapy. Hyperkalemia with succinylcholine occurs in other conditions that upregulate extrajunctional acetylcholine receptors (such as burns, denervation injuries, or severe neuromuscular diseases), not as a direct consequence of lithium treatment. Hence, this option is not true.