Medical assessment of the patient with mental symptoms

[Cami]

Patients with mental complaints or concerns or disordered behavior present in a variety of clinical settings, including primary care and emergency treatment centers. Complaints or concerns may be new or a continuation of a history of mental problems. Complaints may be related to coping with a physical condition or be the direct effects of a physical condition on the brain. The method of assessment depends on whether the complaints constitute an emergency or are reported in a scheduled visit. In an emergency, a physician may have to focus on more immediate history, symptoms, and behavior to be able to make a management decision. In a scheduled visit, a more thorough assessment is appropriate.
Medical assessment of patients with mental symptoms seeks to identify 3 things:

Physical disorders mimicking mental disorders
Physical disorders caused by mental disorders or their treatment
Physical disorders accompanying mental disorders

Numerous physical disorders cause symptoms mimicking specific mental disorders (see table Selected Mental Symptoms Due to Physical Disorders). Other physical disorders may not mimic specific mental syndromes but instead change mood and energy.
Many drugs cause mental symptoms; the most common classes of drug causes are

Central nervous system–active drugs (eg, antiseizure drugs, antidepressants, antipsychotics, sedative/hypnotics, stimulants)
Anticholinergics (eg, antihistamines)
Corticosteroids

Numerous other therapeutic drugs and drug classes have also been implicated; they include some classes that may not ordinarily be considered (eg, antibiotics, antihypertensives). Drugs of abuse, particularly alcohol, amphetamines, marijuana (cannabis), cocaine, hallucinogens, and phencyclidine (PCP), particularly in overdose, are also frequent causes of mental symptoms. Withdrawal from alcohol, barbiturates, or benzodiazepines may cause mental symptoms (eg, anxiety) in addition to symptoms of physical withdrawal.
Patients with a mental disorder may develop an unrelated physical disorder (eg, meningitis, diabetic ketoacidosis) that causes new or worsened mental symptoms. Thus, a clinician should not assume that all mental symptoms in patients with a known mental disorder are due to that disorder. The clinician may need to be proactive in addressing possible physical causes for mental symptoms, especially in patients unable to describe their physical health because they have psychosis or dementia.
Patients presenting for psychiatric care occasionally have undiagnosed physical disorders that are not the cause of their mental symptoms but nonetheless require evaluation and treatment. Such disorders may be unrelated (eg, hypertension, angina) or caused by the mental disorder (eg, undernutrition due to lack of motivation to eat resulting from chronic schizophrenia) or its treatment (eg, hypothyroidism due to lithium , hyperlipidemia secondary to atypical antipsychotics).