Atypical antidepressants for depression
Examples
Generic Name Brand Name bupropion Wellbutrin XL, Wellbutrin SR mirtazapine Remeron trazodone Desyrel, Trazorel venlafaxine Effexor XR These medications are antidepressant medications that do not fit well into any of the other medication categories. They are taken in tablet form (orally).
How It Works
Bupropion, mirtazapine, trazodone, and venlafaxine balance certain brain chemicals (neurotransmitters). When these brain chemicals are balanced, the symptoms of depression are relieved.
Why It Is Used
These medications may be tried when other antidepressants are not effective or have problematic side effects. They may be used on their own or along with another drug.
Sometimes certain selective serotonin reuptake inhibitors (SSRIs) or other antidepressants can cause significant problems with sexual function. Bupropion is less likely to cause sexual dysfunction than other antidepressants, such as SSRIs. When sexual dysfunction side effects occur, bupropion may be prescribed instead of, or in addition to, an SSRI.
Mirtazapine may be useful if you are experiencing insomnia or agitation.
Trazodone is often used along with an SSRI to help with sleep disturbances.
When these drugs are not used
You should not take one of these medicines if you have had an allergic reaction to it in the past or if you have taken a monoamine oxidase inhibitor (MAOI) within the past 2 weeks. If you have taken an MAOI within the past 2 weeks, taking bupropion may cause life-threatening high blood pressure.
You should not take bupropion if you have had a seizure or an eating disorder.
You should not take trazodone if you are recovering from a recent heart attack or have carcinoid syndrome.
Although sometimes used in children, these medications have not been approved for use in people under the age of 18.
How Well It Works
These antidepressants may be as effective as selective serotonin reuptake inhibitors (SSRIs) in treating depression. Bupropion, mirtazapine, trazodone, and venlafaxine are all effective in treating adults. Venlafaxine is not effective in treating children or adolescents who have depression. Experts are still studying whether bupropion is an effective medicine for children or adolescents.
Side Effects
Bupropion, mirtazapine, trazodone, and venlafaxine have different side effects than selective serotonin reuptake inhibitors (SSRIs), cyclic antidepressants, or monoamine oxidase inhibitors (MAOIs).
Trazodone has numerous side effects, and in rare cases, some can be severe.
The most common side effects of each of these medications are listed below.
Bupropion possible side effects
- Weight loss of more than 2.3 kg (5 lb)
- Agitation, confusion, nervousness, and anxiety
In rare cases, bupropion can cause other adverse effects, some of them serious, such as allergic reactions, dry mouth, headaches, heart palpitations, and seizures.
Mirtazapine possible side effects
- Drowsiness
- Increased appetite or weight gain
- Increased cholesterol levels
- Dizziness
- Dry mouth
- Constipation
Other more serious side effects are rare but can include agranulocytosis (insufficient white blood cell count), allergic reactions, and liver or pancreas problems.
Venlafaxine possible side effects
- Constipation
- Headaches
- Weight loss
- Dry mouth
- Slight increase in cholesterol
- Hypertension
- Sexual dysfunction
Side effects when discontinuing venlafaxine can include dizziness, nausea, headache, abnormal touch sensation or tingling (paresthesia), vomiting, irritability, and nightmares.
Trazodone possible side effects
- Drowsiness
- Dizziness or light-headedness
- Blurred vision
- Weight gain
- Dry mouth
- Constipation
- Headache
- Nausea
Side effects may also include priapism, a painful condition in which the penis stays erect. If this happens, call your doctor at once.
Advisories.
- Health Canada and the U.S. Food and Drug Administration (FDA) have issued advisories on antidepressant medicines and the risk of suicide. Health Canada and the FDA do not recommend that people stop using these medicines. Instead, a person taking antidepressants should be watched for warning signs of suicide. This is especially important at the beginning of treatment or when the doses are changed.
- Health Canada and the FDA recommend that patients at risk for glaucoma be watched for signs of pupil dilation (mydriasis) when taking venlafaxine.
Do not stop antidepressant use suddenly. Talk to your health professional about any concerns you may have.
See Drug Reference for a full list of side effects. (Drug Reference is not available in all systems.)
What To Think About
Bupropion may trigger seizures in some people. You will probably want to avoid taking this medication if you have a history of seizures or eating disorders.
You may start to feel better within 1 to 3 weeks of taking antidepressant medicine. But it can take as many as 6 to 8 weeks to see more improvement. If you have questions or concerns about your medicines, or if you do not notice any improvement by 3 weeks, talk to your doctor.
These medications should not be used along with monoamine oxidase inhibitors (MAOIs) because serious, sometimes fatal, reactions can occur. To avoid serious reactions, wait at least 14 days after ending an MAOI treatment before beginning treatment with any one of these medications.
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| Author: | Jeannette Curtis Douglas Dana Ralph Poore | Last Updated: May 14, 2007 |
| Medical Review: | Martin Gabica, MD - Family Medicine Andrew Swan, MD, CCFP, FCFP - Family Medicine Lisa S. Weinstock, MD - Psychiatry | |
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| Topic Contents | |
| Examples | |
| How It Works | |
| Why It Is Used | |
| How Well It Works | |
| Side Effects | |
| What To Think About | |