Major depressive disorder, a condition characterized by intense feelings of sadness and hopelessness, affects approximately 14.8 million adults in the United States, according to the Depression and Bipolar Support Alliance. Depression often occurs in conjunction with other diseases and disorders, including anxiety disorders. Anxiety--feelings of fearfulness or uncertainty that interfere with daily activities--includes obsessive compulsive disorder, panic disorder and social phobias. Doctors prescribe some of the same medications to treat both depression and anxiety.
Selective Serotonin Reuptake Inhibitors
Selective serotonin reuptake inhibitors, or SSRIs, describe a group of medications that inhibit the reabsorption of serotonin, a brain neurotransmitter that affects moods. Medications classified as SSRIs include fluoxetine, sertraline, escitalopram, paroxetine and citalopram.
Doctors commonly prescribe SSRIs to treat depression, as according to MayoClinic.com these medications cause fewer side effects, making them safer than other antidepressants. SSRIs also effectively treat anxiety disorders, including panic disorder, obsessive compulsive disorder, social phobias and post-traumatic stress disorder. Common side effects include decreased sexual desire, nausea, jitters and restlessness.
Tricyclic Antidepressants
Tricyclics, an older class of antidepressants, include imipramine, amitriptyline, amoxapine and clomipramine. For depression, doctors typically prescribe tricyclics after an SSRI fails to provide relief from symptoms. Most tricyclic antidepressants also provide relief for anxiety disorders, with the exception of obsessive compulsive disorder. The National Institute of Mental Health reports that clomipramine is the only tricyclic antidepressant useful for treating obsessive compulsive disorder.
Tricyclic antidepressants' most common effects include weight gain, drowsiness, dry mouth, blurred vision, dizziness, constipation, nausea, weakness and headache. The incidence of serious side effects--including low blood pressure, rapid heart rate and urinary retention--can lead to more severe complications such as glaucoma, enlarged prostate and certain types of heart disease, according to MayoClinic.com.
Monoamine Oxidase Inhibitors
Monoamine oxidase inhibitors, or MAOIs, describe a group of medications that inhibit the actions of the enzyme monoamine oxidase. Monoamine oxidase functions to break down serotonin, norepinephrine and dopamine. Although the oldest of all antidepressant medications, due to their potentially dangerous side effects and interactions, doctors prescribe MAOIs when other medications fail to provide relief.
MAOIs such as tranylcypromine, phenelzine and isocarboxazid can treat both depression and anxiety disorders such as panic disorder and social phobia. Common side effects include drowsiness, dizziness, constipation, nausea, diarrhea, constipation, fatigue and weight gain. Those on MAOIs must follow a strict diet as eating foods containing tyramine, such as aged cheeses, pickled foods, chocolate, certain meats, beer and wine, can cause a dangerously high increase in blood pressure, resulting in a stroke.
Anti-anxiety Drugs
Anti-anxiety drugs include high-potency benzodiazepines such as clonazepam, lorazepam and alprazolam. These drugs can treat generalized anxiety disorder, panic disorder and social phobias. Patients with depression can also benefit from these medications as they can enhance the effects of antidepressants, a strategy known as augmentation, according to MayoClinic.com.
