children may also have concomitant medical problems and, in fact, are at greater risk for presenting with emergent medical conditions such as injuries and ingestions than are nonpsychiatrically ill children A thorough medical history, including current medication and possible ingestions, followed by a complete physical examination, including a complete neurologic examination is all that is required for the majority of patients There is no “standard” set of laboratory evaluations that must be obtained to “clear” a psychiatric patient Patients with new onset of or acute change in psychiatric symptoms, especially psychosis or alterations in mental status, must be carefully evaluated for possible underlying medical conditions These patients may require additional laboratory evaluation or subspecialist consultation In addition, some psychiatric facilities may request or require baseline laboratory data before accepting a transfer Toxicologic screens and pregnancy tests in postpubertal teens are the most frequently obtained laboratory tests Table 126.2 lists laboratory evaluations that may be considered for psychiatric patients TABLE 126.2 SCREENING TESTS FOR MEDICAL ILLNESS Complete blood cell count with differential Complete blood chemistries (including measurements of electrolytes, glucose, calcium, and magnesium levels and tests of hepatic and renal function) Thyroid function tests Pregnancy test Urinalysis Urine and serum toxicology screen EKG Plasma levels of any drugs being taken, if appropriate Neuroimaging (if clinically indicated) 10 Lumbar puncture (if clinically indicated) EKG, electrocardiogram; CT, computed tomography Adapted from Sadock BJ, Sadock VA, eds Kaplan & Sadock’s Synopsis of Psychiatry 9th ed Philadelphia, PA: Lippincott Williams & Wilkins; 2003:24