All about prescription drugs for depression

Antidepressants are used for the treatment of depression, anxiety, and other mental health conditions.  They don’t cure depression, but they’re very effective at reducing symptoms and improving quality of life.  Sometimes the first antidepressant you take will work just fine, but if it doesn’t reduce your symptoms or it causes side effects that bother you, your doctor may discuss switching to another medication or using a combination of antidepressants.

How do doctors know which treatment is right for which patient?

There are many depression medications on the market.  Each works in a slightly different way and can have different side effects.  The doctor chooses a medication by looking at the type of depression the patient has, potential side effects, drug interactions with other medications or medical problems, affordability of the medication, and whether there’s an antidepressant that worked in a close relative.   They will also consider whether the patient has an addiction or is pregnant or breast-feeding, as that can influence the choice of depression medication.

What do all antidepressants have in common?

Studies suggest that all antidepressants are equally effective at treating depression.  One is no better or faster-working than the other.  Albeit rare, all depression medications can cause:

• Suicidal thoughts, especially in children, adolescents, and adults under 25. This is not common and typically happens in the first few weeks after starting or changing the dose.  Risk of increased suicide related to antidepressants is extremely uncommon in adults.   Keep in mind that antidepressants in the long run improve mood and are more likely to reduce suicide risk.
• A life-threatening coma called serotonin syndrome, especially if mixed with MAOI antidepressants. Serotonin syndrome is extremely rare.  This doesn’t happen with Wellbutrin.
• Mania, in people with a tendency towards bipolar disorder. Mania is a euphoric or irritable state of mood associated with too much energy, racing thoughts, speaking too much, impulsiveness, and decreased need for sleep.

What types of depression medications are there?

Antidepressants tend to work by increasing certain chemicals in the brain, especially serotonin, norepinephrine, and dopamine.  Medications are divided into groups according to how they affect these chemicals. The following is a general overview of antidepressants and some associated side effects.

Tricyclic Antidepressants (TCA) have been around longer than all other antidepressants.  In 1951, the TCA Imipramine was the first antidepressant to be discovered.  TCA’s are very effective but have many side effects.  Doctors typically reserve them for patients who have tried other antidepressants without improvement.

• TCA’s work by increasing serotonin and norepinephrine in the brain.
• These medications are used for depression, chronic pain, anxiety, sleep problems.
• Examples are Imipramine (Tofranil), Amitriptyline (Elavil), and Nortriptyline (Pamelor)
• They are sedating, which can help people struggling with insomnia. Side effects can also include weight gain, dry mouth, blurred vision, constipation, problems urinating, fast heart rate, dizziness, fainting, shakiness, sexual side effects (like problems having an erection or orgasm), and (uncommon) confusion, heart problems, and seizures.
• TCA’s are used in pregnancy but aren’t first choice.

Monoamine Oxidase Inhibitors (MAOI) have been available for depression for many years.  They aren’t used as frequently as other antidepressants due to potentially dangerous interaction with certain kinds of food and medications.  MAOI’s are typically reserved for people who don’t respond to all other antidepressants.

• MAOI’s are used for depression and anxiety.
• Examples are Tranylcypromine (Parnate), Phenelzine (Nardil), and Selegiline (Emsam)
• Side effects vary from drug to drug. Tranylcypromine causes weight loss and insomnia. Phenelzine causes dry mouth, sexual side effects, weight gain, and sleepiness. Selegiline has fewer side effects than other MAOI’s.  All can cause dizziness.
• MAOI’s Interact with foods containing tyramine, like aged cheese and meats, sausage, pickles, wine, beer, and avocado. Tyramine causes a “hypertensive crisis,” which involves very high blood pressure, headache, dizziness, nausea, and potential damage to the brain, kidneys, and other organs.
• MAOI’s interact with other antidepressants, St. John’s Wort, some pain killers, decongestants, and other medications. There aren’t many studies using MAOI’s in pregnancy.
• Selegiline is an MAOI that comes in a patch form you can stick on your skin. It has fewer food and medication interactions than other MAOI’s.

Selective Serotonin Reuptake Inhibitors (SSRI) are often a doctor’s first choice for a patient with depression because they have fewer bothersome side effects.

• SSRI’s target depression by increasing serotonin levels in the brain
• SSRI’s are used for depression & anxiety. Fluoxetine is also used for bulimia.
• Examples are Paroxetine (Paxil), Fluoxetine (Prozac), and Sertraline (Zoloft).
• Side effects vary from medication to medication, but in general they include slight tremor, temporary stomach upset, problems sleeping or sleeping too much, sexual side effects, weight loss or weight gain, and (rarely) gastrointestinal bleed. Elderly patients can occasionally develop confusion from sodium level abnormalities.
• SSRI’s are first choice in pregnancy, except for Paxil.

Serotonin Norepinephrine Reuptake Inhibitors (SNRI) are activating antidepressants that are typically taken in the morning.

• SNRI’s increase both serotonin and norepinephrine in the brain..
• They are used for depression, anxiety, chronic pain, and occasionally attention problems.
• Examples are Venlafaxine (Effexor), Duloxetine (Cymbalta), and Desvenlafaxine (Pristiq)
• Side effects are similar to those of the SSRI’s. Venlafaxine is sometimes associated with high blood pressure.  Duloxetine can rarely cause liver disease.
• SNRI’s are sometimes used in pregnancy when SSRI’s aren’t an option.

Atypical or miscellaneous antidepressants include medications that don’t fit neatly into any of the other depression medication categories.  This group varies in terms of how they work and potential side effects.

• Buproprion (Wellbutrin, Zyban) is used for depression, attention problems, and smoking cessation. It increases dopamine and norepinephrine in the brain.  It is an activating medication and usually taken in the morning.  Side effects include anxiety, shakiness, headache, constipation, dry mouth, sleep problems, and rarely seizures.  It doesn’t cause sexual side effects. Bupropion should be avoided in people with severe alcoholism, eating disorders, epilepsy, and traumatic brain disorder.

• Mirtazapine (Remeron) is used for depression and insomnia. It has an unusual mechanism of action, targeting norepinephrine alpha receptors, different to other antidepressants.  Mirtazapine is sedating, which can help with sleep.  Side effects include weight gain and potential falls when sedated.  It doesn’t cause sexual side effects.
• Trazodone (Desyrel) is a medication typically used for sleep.  It becomes an antidepressant at high doses, but most people get too sleepy at this high dose.  Side effects include sleeping too much, feeling sleepy in the morning, blurred vision, constipation, dizziness, potential falls when dizzy or sleepy, weight gain, fast heart rate,  and (very rarely) a painful erection that won’t go away without medical treatment.  It isn’t safe for pregnancy.
• Nefazodone (Serzone) is rarely used these days due to the potential for damage to the liver. Side effects include sleepiness, dizziness, falls when sleepy, weight loss, headaches, constipation.  It has no sexual side effects.  There aren’t many studies using Nefazodone in pregnancy.
• Vortioxetine (Trintellix) is a new medication on the market for depression and anxiety. Its side effects are similar to the SSRI’s.  There are almost no studies using Vortioxetine in pregnancy.