Antidepressants

There are several different kinds of antidepressants. All of them are effective in relieving the symptoms of depression, but no one antidepressant works for everybody who is depressed. Different types of antidepressants also tend to have different kinds of side effects. In the lists below, the first name is the antidepressant’s scientific or generic name, followed in parentheses by its brand, or proprietary, name. We list typical doses for each medication, but doses vary widely from person to person. Doses are typically lower for people over age 60 or those with a chronic medical illness. All of the drugs in this section should be taken according to the dose and manner prescribed by your doctor.

Serotonin Reuptake Inhibitors (SRIs)

The newest antidepressants have quickly become quite popular. Known as selective serotonin reuptake inhibitors (SRIs), they work by increasing the amount of the neurotransmitter serotonin available in the brain. SRIs are chemically unrelated to the tricyclics and are considered to have fewer and more tolerable side effects than many of the older antidepressants.

Common SRIs

Fluoxetine (Prozac): Fluoxetine was the first, and is still the best known, of the SRIs. Common side effects include nausea, gastrointestinal irritability, headaches, jitteriness, decreased ability to achieve orgasm, and insomnia. Switching to a different antidepressant is required in 5 to 15 percemt of patients. Effective dosages range from 20 to 60 mg.

Fluvoxamine (Luvox): Common side effects include nausea, gastrointestinal irritability, headaches, jitteriness, decreased ability to achieve orgasm, and insomnia. Switching to a different antidepressant is required in 5 to 15 percent of patients. Effective dosages range from 100 to 300 mg.

Paroxetine (Paxil): Common side effects include nausea, gastrointestinal irritability, headaches, jitteriness, decreased ability to achieve orgasm, and insomnia. Switching to a different antidepressant is required in 5 to 15 percent of patients. Effective dosages range from 20 to 60 mg.

Sertraline (Zoloft): Common side effects include nausea, gastrointestinal irritability, headaches, jitteriness, decreased ability to achieve orgasm, and insomnia. Switching to a different antidepressant is required in 5 to 15 percent of patients. Effective dosages range from 50 to 200 mg.

Citalopram (Celexa): Common side effects include nausea, gastrointestinal irritability, headaches, jitteriness, insomnia, and decreased ability to achieve orgasm. Switching to a new antidepressant is required in 5 to 15 percent of patients. Effective dosages range from 20 to 60 mg.

Escitalopram (Lexapro): Common side effects include nausea, gastrointestinal irritability, headaches, jitteriness, insomnia, and decreased ability to achieve orgasm. Switching to a new antidepressant is required in 5 to 15 percent of patients. Effective dosages range from 10 to 30 mg.

Common Serotonin-Norepinephrine Inhibitors

Venlafaxine (Effexor): This antidepressant increases the amount of both serotonin and norepinephrine available at nerve synapses in the brain. Venlafaxine sometimes causes dry mouth, dizziness, constipation, urinary hesitancy, and blurred vision. It can also cause sexual side effects, but probably does so less often than most SRI medications. In about 5 percent of patients, venlafaxine can raise blood pressure. It has also been shown to be effective in treating neuropathic pain from diabetes. Effective dosages range from 75 to 300 mg.

Duloxetine (Cymbalta): This antidepressant increases the amount of serotonin and norepinephrine available at nerve synapses in the brain. Duloxetine sometimes causes dry mouth, dizziness, and nausea. It can also cause sexual side effects, but probably less often than other SRI medications. It has also been shown to be effective in treating neuropathic pain from diabetes. Effective dosages range from 60 to 120 mg.

Other Newer Antidepressants

Bupropion (Wellbutrin): This medication is different from most other antidepressants; it may work by increasing the action of dopamine, another neurotransmitter. Common side effects include jitteriness, nausea, and sleep disturbances. Because large doses at a single time can slightly increase the risk of seizures or convulsions, it is usually taken two times per day. Effective dosages range from 200 to 450 mg.

Mirtazapine (Remeron): This antidepressant also increases the action of serotonin and norepinephrine, but it does not have as frequent sexual side effects as the SRI medications described above. Common side effects include sedation, dizziness, weight gain, and dry mouth. Effective dosages range from 30 to 60 mg.

Tricyclic (or Heterocyclic) Antidepressants

Tricyclics, developed in the late 1950s and early 1960s, were the first antidepressants. Most of them work by increasing the amount of the neurotransmitters norepinephrine and (to a lesser extent) serotonin available at synapses, the tiny spaces between nerve cells, in the brain. As a group, the tricyclics tend to produce the following side effects: dry mouth, constipation, hesitancy in urinating, blurred vision, sleepiness, weight gain, dizziness when changing quickly from a lying or sitting position to standing up (postural hypotension), and increased heart rate or pulse rate. For most people, these side effects are tolerable, but in about 10 to 20 percent of cases, a switch to a different antidepres-sant is required.

Commonly Prescribed Tricyclics

Amitriptyline (Elavil): One of the earliest antidepressants. Common side effects include dry mouth, constipation, urinary hesitancy, blurred vision, sedation, weight gain, postural hypotension, and increased heart or pulse rate. Effective dosages range from 50 to 300 mg.

Desipramine (Norpramin): This drug’s side effects tend to be less troublesome than those of the older tricyclics such as imipramine or sinequan, but they are similar in kind: dry mouth, constipation, urinary hesitancy, blurred vision, sedation, weight gain, postural hypotension, increased heart rate, and rash. For most patients, these side effects are tolerable, but in 5 to 15 percent of cases, a switch to a different medication is required. Effective dosages range from 50 to 300 mg.

Imipramine (Tofranil): One of the first tricyclics. Common side effects include dry mouth, constipation, urinary hesitancy, blurred vision, sedation, weight gain, postural hypotension, and increased heart or pulse rate. Effective dosages range from 50 to 300 mg.

Nortriptyline (Pamelor): Nortriptyline’s side effects are less severe than those of most other tricyclic antidepressants. Side effects include sleepiness, dry mouth, constipation, urinary hesitancy, blurred vision, weight gain, postural hypotension, and increased heart or pulse rate. In 5 to 15 percent of patients, side effects require switching medication. Effective dosages range from 50 to 150 mg.

Protriptyline (Vivactil): Protriptyline causes increased energy and, as a result, is usually taken in the morning. In addition to the usual side effects associated with tricyclics, protriptyline can cause jitteriness. Effective dosages range from 10 to 40 mg.

Doxepin (Sinequan): Doxepin is one of the antidepressants most likely to cause sedation. Other common side effects include dry mouth, constipation, urinary hesitancy, blurred vision, weight gain, postural hypotension, and increased heart or pulse rate. Effective dosages range from 50 to 300 mg.

Other Heterocyclic Agents

Amoxapine (Asendin): Amoxapine is not usually recommended except for depressed patients with psychotic symptoms, such as hallucinations or delusions. It increases the amount of norepinephrine and (to a lesser extent) serotonin available at nerve synapses in the brain. Possible side effects include those common to the tricyclics. In rare cases, it can cause long-term problems with muscle twitching or spasms. Effective dosages range from 50 to 300 mg.

Maprotiline (Ludiomil): This medication increases the amount of the neurotransmitter norepinephrine available at nerve synapses in the brain. Its side effects are the usual ones seen with tricyclic antidepressants. For most patients its side effects are mild to moderate, but in 5 to 15 percent of cases, they require changing medication. Ludiomil does slightly increase the risk of seizures or convulsions. Effective dosages range from 50 to 200 mg.

Trazodone (Desyrel): Trazodone has been available for about 15 years. It increases the amount of serotonin available at synapses in the brain. Side effects include sedation, postural hypotension, and weight gain. A more severe (but rare) side effect is priapism, a prolonged erection. Because of its sedating properties, trazodone is sometimes used in low doses for the treatment of insomnia. Most patients can tolerate its side effects, but about 5 to 15 percent switch to another antidepressant. Effective dosages range from 50 to 300 mg.

MAO Inhibitors

Monoamine oxidase (MAO) inhibitors affect mood by increasing the amount of the neurotransmitters norepinephrine, epinephrine, and serotonin available at synapses in the brain. MAO inhibitors are often prescribed when other antidepressants have not been successful. Patients taking MAO inhibitors must avoid certain foods, especially those containing tyramine, a chemical that helps regulate blood pressure. Tyramine is found in foods such as bananas, herring, chicken livers, avocados, and eggplant, as well as in beer and wine and in aged foods like dried sausage and cheese. Over-the-counter diet, cold, and asthma medications, among others, are also off limits when taking most MAO inhibitors. Check with your doctor or pharmacist for a complete list of things to avoid if you are taking one of the drugs in this class.

Common MAO Inhibitors

Phenelzine (Nardil): Common side effects include fatigue, weakness, postural hypotension, restlessness, tremors, dry mouth, constipation, urination difficulties, blurred vision, and “sweet tooth.” Effective dosages range from 15 to 60 mg.

Tranylcypromine (Parnate): Common side effects include fatigue, weakness, postural hypotension, restlessness, tremors, dry mouth, constipation, urination difficulties, blurred vision, and “sweet tooth.” Effective dosages range from 10 to 30 mg.

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