However, a potentially life threatening condition called serotonin syndrome may occurred with nortriptyline, either taken alone or with MAOIs (or monoamine
oxidase inhibitors) and/or other serotonergic drugs, such as triptans, tricyclic antidepressants, tramadol, and etc.
Serotonin syndrome symptoms may include: tachycardia (or fast heart beat), labile blood pressure, dizziness, flushing, tremor, etc.