How Long It Takes for Antidepressants to Work

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If you have been prescribed an antidepressant medication to help reduce the symptoms of depression and anxiety, you may be wondering how long it will take for the antidepressant to work. Read ahead to learn more about antidepressants, including how long they may take to work.

What Are Antidepressants?

As you can tell by the name, antidepressants are used to treat the symptoms of depression. This class of medication has also been found to effectively reduce the symptoms of many other mood and anxiety disorders, including obsessive-compulsive disorder (OCD), bipolar disorder, social anxiety disorder (SAD), agoraphobia. Additionally, antidepressants have become the usual medications to treat panic disorder.

There are different types or classes of antidepressants that impact chemical messengers in the brain. Known as neurotransmitters, these messengers are responsible for a variety of bodily functions and feelings, including sleep and mood regulation, anxiety levels, and motivation. Common classes of antidepressants used to treat anxiety-related disorders include:

  • Serotonin and Norepinephrine Reuptake Inhibitors (SNRIs)
  • Selective Serotonin Reuptake Inhibitors (SSRIs
  • Tricyclic antidepressants (TCAs)​
  • Monoamine Oxidase Inhibitors (MAOIs)

How Long Antidepressants Take to Be Effective

Studies have shown that antidepressants are effective in reducing or eliminating panic attacks and improving anticipatory anxiety and symptoms of agoraphobia. Unfortunately, antidepressants generally don’t result in immediate relief of symptoms. Most people will not see a significant improvement for at least 4 weeks.

Studies have generally shown that the full benefits of antidepressant therapy may take as long as 8 to 12 weeks. However, this timeline is variable among individuals. For people with severe anticipatory anxiety and agoraphobic avoidance, symptoms may not show significant improvement for 6 months or longer—severe disease is simply harder to treat and will take more time.

What to Expect When Taking Antidepressants

Some people may experience increased nervousness or anxiety at the beginning of antidepressant therapy. To reduce this possibility, your doctor may start you at a very low dose that is gradually increased. Some of the most common side effects of taking antidepressants include:

  • Sleep disturbances
  • Headaches
  • Fatigue
  • Dizziness
  • Lightheadedness
  • Dry mouth
  • Nervousness
  • Increased sweating
  • Sexual side effects
  • Blurred vision
  • Nausea

This list is only some of the side effects you can face while taking an antidepressant. You may experience one or more of these side effects, or you may not have to deal with any of them. These side effects typically subside and become much more manageable over time. If side effects are persistent and become difficult to manage, you can always consult your doctor about the possibility of changing the dosage or medication to better fit your needs.

Your doctor may also prescribe a benzodiazepine (anti-anxiety medication) along with your antidepressant, especially in the beginning of treatment. Benzodiazepines provide quick relief, allowing for a faster sense of tranquility. However, these medications have the potential for much more challenging side effects, including the potential for addiction. To reduce this risk, your doctor may take you off the benzodiazepine once the antidepressant reaches its full benefit.

If you and your doctor believe that you have had an adequate trial of antidepressant therapy without significant improvement of symptoms, a medication change may be made. For the vast majority of panic disorder sufferers, the right medication will be found to improve or eliminate panic symptoms.

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Article Sources

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Additional Reading

  • American Psychiatric Association. Practice Guidelines for the Treatment of Psychiatric Disorders: Compendium 2006. American Psychiatric Association, 2006.