It occurs most often in patients with panic disorder.

It involves treatment with noradrenergic medications such as desipramine and imipramine.

Nervousness, restlessness, tremulousness, fever, agitation, difficulty in concentrating, insomnia, increased anxiety.

Symptoms occur when the medications are started.

Symptoms are usually transient.

By the time the medication is therapeutic (several weeks after the medication is started), the symptoms will have resolved.

Symptoms may be so uncomfortable that the patient might discontinue the medication very early in treatment.

Start patients with panic disorder on low doses (10-20 mg of imipramine or desipramine a day).

Gradually increase dose to 150 mg per day.