What is the likely diagnosis and recommended treatment for a 19-year-old patient with a one-week history of sleepless nights, excessive energy, and a family history of bipolar disorder, given their relative has bipolar disorder?

Likely Diagnosis: Bipolar I Disorder, Manic Episode

This 19-year-old patient with one week of sleeplessness, excessive energy, and a first-degree relative with bipolar disorder most likely has a manic episode consistent with Bipolar I Disorder, and requires immediate initiation of antimanic pharmacotherapy with lithium, valproate, or an atypical antipsychotic. 1, 2

Diagnostic Rationale

The clinical presentation strongly suggests a manic episode based on:

• Duration criterion met: Symptoms lasting one week fulfill DSM criteria for mania (minimum 7 days required) 1, 3
• Decreased need for sleep: The patient has "sleepless nights" yet "feels like they have a lot of energy"—this is the hallmark differentiating feature of mania where patients sleep less but feel rested and energized, not simply insomnia 1, 3
• Increased energy/psychomotor activation: The excessive energy represents a distinct change from baseline functioning 1, 3
• Strong genetic loading: First-degree relatives of individuals with bipolar disorder have a 4-6 fold increased risk, making this diagnosis highly probable given the family history 1

Critical Screening Questions to Confirm Diagnosis

Before finalizing the diagnosis, you must ask:

• Mood elevation: "Have you felt extremely happy, 'high,' or irritable—very different from your normal self—during this past week?" 1, 3
• Grandiosity: "Have you felt like you have special powers or abilities, or that you're more important than usual?" 1
• Racing thoughts/pressured speech: "Are your thoughts racing? Do others say you're talking much more or faster than usual?" 1, 3
• Increased goal-directed activity: "Have you been starting lots of new projects or activities?" 1
• Risky behavior: "Have you done things that are risky or that you wouldn't normally do, like spending lots of money or engaging in risky sexual behavior?" 1
• Functional impairment: "Has this caused problems at school, work, or with relationships?" 1

Essential Differential Considerations

Rule out substance-induced mood disorder first: Obtain toxicology screening immediately, as approximately 20% of apparent manic presentations may be substance-induced 1. Ask specifically about:

• Stimulants (cocaine, methamphetamine, prescription stimulants)
• Cannabis, hallucinogens
• Recent antidepressant use (can precipitate mania in bipolar patients) 1

Medical workup required: Complete thyroid function tests, CBC, and comprehensive metabolic panel to exclude organic causes (hyperthyroidism, CNS lesions) before confirming psychiatric diagnosis 1

Common Diagnostic Pitfalls to Avoid

• Don't confuse chronic irritability with episodic mania: True manic irritability represents a marked change in mental state during a distinct time period, not temperamental traits or reactions to conflict 1, 3
• Don't rely on irritability alone: Irritability is nonspecific and occurs across multiple diagnoses including ADHD, disruptive behavior disorders, and PTSD 1
• Don't miss the sleep pattern: Verify this is reduced need for sleep (feeling rested despite minimal sleep) rather than insomnia (wanting to sleep but unable) 3

Immediate Treatment Recommendations

Pharmacotherapy is the primary treatment for acute mania in well-defined Bipolar I Disorder 4. Start immediately with one of these FDA-approved first-line agents:

First-Line Medication Options:

1. Lithium (FDA-approved for acute mania down to age 12): Expected normalization of symptoms within 1-3 weeks 2. Lithium also reduces suicide attempts 8.6-fold and completed suicides 9-fold 5

2. Valproate (FDA-approved for acute mania in adults): Effective antimanic agent 4, 6

3. Atypical antipsychotics: Aripiprazole, olanzapine, risperidone, quetiapine, or ziprasidone (all FDA-approved for acute mania) 4, 6

Medication Selection Criteria:

Choose based on 4:

• Side effect profile and safety (critical at age 19)
• Patient/family preferences
• Family history of treatment response (parental response may predict offspring response)
• Presence of psychotic symptoms (favors antipsychotic)

Avoid antidepressant monotherapy: Antidepressants can precipitate or aggravate manic symptoms and are contraindicated 7, 8

Monitoring and Follow-Up

• Schedule follow-up within 1-2 weeks to assess medication response, side effects, and adherence 5
• Assess suicidality at every visit: Bipolar disorder has an annual suicide rate of 0.9% (64 times higher than general population), with 15-20% lifetime suicide mortality 1, 6
• Monitor for substance abuse: Rates are particularly high in adolescents with bipolar disorder 1
• Arrange psychoeducation: Helps with medication adherence (critical, as >90% of nonadherent adolescents relapse vs. 37.5% of adherent patients) 5

Long-Term Considerations

• Maintenance therapy required: Continue mood stabilizers for at least 12-24 months after stabilization to prevent recurrence 5, 6
• Expect depressive episodes: Approximately 75% of symptomatic time consists of depressive episodes, which will require different treatment strategies 6, 8
• Annual physical health monitoring: Screen for metabolic syndrome, weight gain, lipid abnormalities, diabetes, smoking, and cardiovascular risk factors 7, 6