A physician-validated, board-style question from the Active Transport QBank. Try it, then check the reasoning for every option.
A 58-year-old man with a past medical history of diabetes, hypertension, and hyperlipidemia was brought into the emergency department by his wife after she observed him go without sleep for several days and recently open and max out several credit cards. She also reports that he has quit his bartending job and has been excessively talkative and easily annoyed for the last several weeks. The patient has no previous psychiatric history. Routine medical examination, investigations, and toxicology rule out a medical cause or substance abuse. Lab results are consistent with chronically impaired renal function. What is the single best treatment for this patient?
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A
Valproic acidCorrect. Valproic acid is an effective first-line agent for acute mania, hepatically metabolized, and a better choice than lithium in this patient with renal impairment.
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B
LithiumIncorrect. Lithium is highly effective for bipolar mania but is renally excreted and nephrotoxic — contraindicated/cautious in this patient with chronic renal impairment.
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C
PregabalinIncorrect. Pregabalin treats neuropathic pain and anxiety; it is not a mood stabilizer for bipolar disorder.
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D
LamotrigineIncorrect. Lamotrigine is more useful in bipolar depression and maintenance, not acute mania, and requires slow titration to avoid Stevens-Johnson syndrome.
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E
RisperidoneIncorrect. Second-generation antipsychotics like risperidone can adjunctively treat acute mania with psychotic features, but valproic acid is the preferred single-agent first-line mood stabilizer in renal impairment.
↑ Tap an answer to reveal the reasoning
Answer: A. A 58-year-old man with no prior psychiatric history but new-onset decreased need for sleep, hyperverbal pressured speech, irritability, grandiosity (maxing out credit cards), impulsivity, and goal-directed behavior (quit job) over several weeks meets criteria for a manic episode of bipolar I disorder. Medical/substance causes have been ruled out. Treatment requires a mood stabilizer. The choice of stabilizer must take his comorbidities into account: he has chronically impaired renal function.
Lithium is the classic first-line mood stabilizer for bipolar disorder but is excreted unchanged by the kidneys and is nephrotoxic with long-term use — it is contraindicated or strongly cautioned in patients with impaired renal function. Valproic acid (divalproex) is an excellent alternative first-line agent for acute mania; it is hepatically metabolized, doesn't require renal dose adjustment, and is generally well tolerated. Lamotrigine is more useful for bipolar depression and maintenance than acute mania. Pregabalin is used for neuropathic pain and anxiety, not bipolar disorder.
Key pearl: choose mood stabilizers based on patient comorbidities — valproate for renal disease, avoid lithium in renal impairment, avoid valproate in liver disease and pregnancy (teratogen), lamotrigine for bipolar depression but watch for Stevens-Johnson syndrome.
**Why each option:**
**A.** Correct. Valproic acid is an effective first-line agent for acute mania, hepatically metabolized, and a better choice than lithium in this patient with renal impairment.
**B.** Lithium is highly effective for bipolar mania but is renally excreted and nephrotoxic — contraindicated/cautious in this patient with chronic renal impairment.
**C.** Pregabalin treats neuropathic pain and anxiety; it is not a mood stabilizer for bipolar disorder.
**D.** Lamotrigine is more useful in bipolar depression and maintenance, not acute mania, and requires slow titration to avoid Stevens-Johnson syndrome.