Psychiatric Medications Q 63
The psychiatrist orders lithium carbonate 600 mg p.o t.i.d for a female client. Nurse Katrina would be aware that the teaching about the side effects of this drug were understood when the client state, “I will call my doctor immediately if I notice any:
A. Sensitivity to bright light or sun.
B. Fine hand tremors or slurred speech.
C. Sexual dysfunction or breast enlargement.
D. Inability to urinate or difficulty when urinating.
Correct Answer: B. Fine hand tremors or slurred speech
These are common side effects of lithium carbonate. Lithium can cause several adverse effects. Typically the side effects are dose-related. Notable side effects include confusion, memory problems, new or worsening tremor, hyperreflexia, clonus, slurred speech, ataxia, stupor, delirium, coma, and seizures (rarely). These effects are theoretically due to excess action on the same sites that mediate therapeutic action.
Option A: Lithium does not cause photosensitivity. Some patients on haloperidol and lithium may develop an encephalopathic syndrome similar to neuroleptic malignant syndrome. Other side effects include acne, rash, and weight gain. Lithium-induced weight gain is more common in women than in men.
Option C: Lithium toxicity can cause interstitial nephritis, arrhythmia, sick sinus syndrome, hypotension, T wave abnormalities, and bradycardia. Rarely, toxicity can cause pseudotumor cerebri and seizures. The mechanism of action of lithium is not known. It is rapidly absorbed, has a small volume of distribution, and is excreted in the urine unchanged (there is no metabolism of lithium).
Option D: Lithium toxicity has no antidote. Treatment for lithium toxicity is primarily hydration and to stop the drug. Give hydration with normal saline, which will also enhance lithium excretion. Avoid all diuretics. If the patient has severe renal dysfunction or failure, or severely altered mental status, then start with hemodialysis. 20 to 30 mg of propranolol given 2 to 3 times per day may help reduce tremors.