trazodone

Trazodone is an oral antidepressant drug that affects the chemical messengers (neurotransmitters) within the brain that nerves use to communicate with (stimulate) each other. The major neurotransmitters are acetylcholine, norepinephrine, dopamine, and serotonin.

Many experts believe that an imbalance among the different neurotransmitters is the cause of depression. Although the exact mechanism of action of trazodone is unknown, it probably improves symptoms of depression by inhibiting the uptake of serotonin by nerves in the brain. This results in more serotonin to stimulate other nerves.

Trazodone is approved for the treatment of major depression. However, it is most commonly used for treating insomnia. Trazodone is also used off-label for treating:

• Cocaine withdrawal
• Alcohol withdrawal
• Prevention of migraine

Trazodone also may increase the action of serotonin directly. Trazodone is chemically unrelated to selective serotonin reuptake inhibitors (SSRIs), tricyclic antidepressants (TCAs), or monoamine oxidase inhibitors (MAO inhibitors). It is chemically related to nefazodone (Serzone) and shares its actions. The FDA approved trazodone in 1981.

The most common side effects of trazodone are:

1. Nausea
2. Vomiting
3. Dizziness
4. Insomnia
5. Agitation
6. Tiredness
7. Dry mouth
8. Constipation
9. Weight change
10. Decreased libido

Priapism, (including clitoral priapism in women) a painful condition in which the penis (or clitoris) remains in an erect position for a prolonged period has been reported in people taking trazodone. Priapism occasionally results in permanent impairment of erectile function or impotence. Patients should be warned of the possibility of priapism and told to discontinue the drug at once and consult with their doctor if this reaction occurs.

Trazodone may affect ejaculation, orgasm, and libido.

Antidepressants increased the risk of suicidal thinking and behavior (suicidality) in short-term studies in children and adolescents with depression and other psychiatric disorders. Anyone considering the use of trazodone or any other antidepressant in a child or adolescent must balance this risk with the clinical need. Patients who are started on therapy should be closely observed for clinical worsening, suicidality, or unusual changes in behavior.

For the treatment of depression, the dose for adults is 150-600 mg per day of regular tablets.

• The initial starting dose usually is 150 mg per day, which is increased by 50 mg/day every 3-7 days.
• Trazodone regular tablets are given in one or more daily doses, sometimes with the largest dose at night.
• The dose of extended-release tablets is 150 mg at bedtime initially which is increased by 75 mg/day every 3 days. Extended-release tablets should be swallowed whole and not crushed or chewed. The maximum dose is 375 mg daily.
• As with all antidepressants, it may take several weeks for the full effects of treatment to be seen. Doses often are adjusted slowly upwards to find the amount of dose.
• Elderly patients and debilitated persons may need lower doses.
• Trazodone should be taken after a meal or light snack to reduce the risk of dizziness. Food also increases the number of drugs absorbed into the body.
• Doses of 25-75 mg are prescribed for insomnia.

All antidepressants that increase concentrations of serotonin in the brain, including trazodone, should not be taken with MAO inhibitors. Drugs in the MAO-inhibitor class include:

• isocarboxazid (Marplan)
• phenelzine (Nardil)
• tranylcypromine (Parnate)
• procarbazine (Matulane)

Drugs in the MAOI class can lead to confusion, high blood pressure, and tremors. This same type of interaction may occur when trazodone is used with selegiline (Eldepryl). If a patient is switched from trazodone to an MAO inhibitor, allow at least one week after stopping trazodone before taking the MAO inhibitor.

Increased blood concentrations of digoxin (Lanoxin) and phenytoin (Dilantin) have been reported in persons taking trazodone due to a decrease in the metabolism (breakdown and elimination) of these drugs by trazodone.

Carbamazepine (Tegretol) may decrease blood levels of trazodone by increasing its elimination from the body. Ketoconazole (Nizoral), ritonavir (Norvir), and indinavir (Crixivan) inhibit the breakdown of trazodone leading to increased blood levels of trazodone and potential side effects.

Drugs that increase serotonin may cause bleeding. Therefore, combining trazodone with aspirin, nonsteroidal anti-inflammatory drugs, warfarin (Coumadin, Jantoven), or other drugs that affect bleeding may increase the likelihood of upper gastrointestinal bleeding.

• There are no adequate studies on trazodone in pregnant women. Studies in animals have demonstrated effects on the developing fetus. Trazodone should only be used during pregnancy if the physician feels its benefits outweigh its potential risks.
• Trazodone is secreted in breast milk. Therefore, caution should be used in prescribing trazodone to breastfeeding women.

• Trazodone is available as:
  • Tablets: 50, 100, 150, and 300 mg.
  • Tablets (Extended Release): 150 and 300 mg.
• Trazadone should be stored at room temperature, 15 C to 30 C (59 F to 86 F).
• Trazadone is available in generic form. You need a prescription from your doctor to obtain it.
• The brand name for trazadone was Desyrel.
• The FDA approved trazodone in 1981.