Medically reviewed by Jill Johnson, DNP, APRN, FNP-BC
Written by Our Editorial Team
Last updated 12/8/2021
If you’ve been diagnosed with major depressive disorder, seasonal affective disorder or another form of depressive illness, your healthcare provider may prescribe antidepressants to help you deal with the symptoms of your depression.
Antidepressants help to improve your moods and feelings. They’re effective for most people, but their results aren’t immediate.
Below, we’ve explained how antidepressants work as treatments for depression and anxiety, as well as how long it usually takes for antidepressants to start working.
Antidepressants work by increasing levels of neurotransmitters in your brain and body.
Although a variety of factors play a role in depression, experts believe that one major cause is a reduction in the levels of certain neurotransmitters that regulate your mood, feelings and some aspects of your behavior.
Although antidepressants are usually associated with depression, they’re commonly prescribed to treat anxiety disorders and other mental health conditions.
Several different types of antidepressants are used to treat depression and anxiety:
Selective serotonin reuptake inhibitors (SSRIs). SSRIs are the most commonly used antidepressants on the market, and work by increasing levels of serotonin, an important neurotransmitter that’s involved in regulating your moods and feelings.
Serotonin-norepinephrine reuptake inhibitors (SNRIs). SNRIs are similar to SSRIs, but they also increase levels of the neurotransmitter norepinephrine. Some SNRIs are used to treat pain disorders in addition to depression and anxiety.
Monoamine oxidase inhibitors (MAOIs). An older class of antidepressants, MAOIs are often used when other antidepressants aren’t effective. Many MAOIs can cause serious drug interactions and have a high risk of causing side effects.
Tricyclic antidepressants (TCAs). Another older class of medications, TCAs are often used when newer antidepressants, such as SSRIs, aren’t effective. Some TCAs have a higher risk of side effects than newer SSRIs and SNRIs.
In certain cases, you may be prescribed an atypical antidepressant. Our guide to antidepressants provides more information on the most common antidepressants prescribed to treat depression and anxiety.
Antidepressants work well for most people, but they don’t produce overnight changes in the way you feel, think and behave. In short, they’re not an on-off switch for depression.
Most of the time, antidepressants take two to four weeks to start working.
During the first weeks of using an antidepressant, you may notice that some of your depressive symptoms improve at a faster pace than others. For example, it’s common for your appetite, sleep habits and ability to focus on tasks to improve before you notice any significant improvements in your moods and feelings.
It’s helpful to understand that during the first few months of treatment, the primary goal of treatment with antidepressants is to relieve your depressive symptoms. You may gradually notice that your symptoms are becoming less severe, or that you have fewer negative thoughts or “empty” feelings.
It’s important to continue using your medication even after your mood improves. Your healthcare provider may recommend continuing treatment for several months in order to ensure you’re fully recovered and reduce your risk of experiencing a depression relapse.
Since antidepressants can take several weeks to start working, it’s important to not make any decisions about how effective your medication might be during the first few weeks of treatment.
Instead, focus on taking your medication as prescribed. If you don’t notice any improvements in your depression symptoms after several weeks, it’s best to get in touch with your mental health provider to let them know.
Your mental health provider may adjust your dose of medication, switch you to a different type of antidepressant or make other changes to your treatment.
For some forms of depression or related mental disorders, such as severe depression or bipolar disorder, your mental health provider might prescribe additional medication to help you deal with your symptoms.
It can take some time to get the right “fit” with antidepressants, and it’s far from uncommon to try several medications before finding one that works for you.
Most people experience improvements from medication alone. However, combining medication with therapy, lifestyle changes and other techniques may improve your symptoms and help you more fully recover from depression or anxiety.
Your healthcare provider may recommend trying one of the following approaches to get the best results from your antidepressant.
Although antidepressants are usually effective, they’re not the only option available for treating depression and anxiety. You might get better results if you combine antidepressants with other treatments, such as psychotherapy or lifestyle changes.
Several forms of therapy are used to treat depression, such as cognitive-behavioral therapy, or CBT. Taking part in therapy can help you improve the way you think and better deal with the symptoms of depression.
Beyond medication and therapy, making small changes to your habits and lifestyle can have a significant impact on the way you feel.
Try to keep yourself active and exercise regularly, even if it’s just a short walk around your local neighborhood. Spending time with friends and family and setting goals for your recovery may also help you make progress.
Our guide to helping depression shares 11 methods you can use to improve your thoughts, feelings and quality of life while you’re recovering from depression.
Antidepressants are generally effective, but not everyone experiences the same benefits from medication. In fact, it’s common to try several antidepressants before finding one that best fits your specific symptoms and needs.
If you think your antidepressant isn’t working, inform your healthcare provider. They may make changes to your dosage or suggest switching to a different type of antidepressant medication.
If you think your antidepressant isn’t working, don’t abruptly stop taking it without first talking to your healthcare provider.
When you suddenly stop using an antidepressant, you run the risk of developing antidepressant discontinuation syndrome, which includes a range of symptoms that can affect both your physical and mental health.
If you want to stop using your medication, let your healthcare provider know. They may suggest gradually tapering your dosage or other changes to safely stop using your medication.
Antidepressants can cause side effects. Common side effects of antidepressants include sleep difficulties, nausea, drowsiness, dry mouth, sweating, weight gain and changes that affect your sex drive and sexual performance.
Most of the time, side effects from antidepressants appear within the first few weeks of use and get better over time.
In rare cases, antidepressants may cause more severe side effects. Make sure to inform your healthcare provider if you experience any side effects from your medication, especially if they are severe or persistent.
Major depression is a serious mental illness that can affect every aspect of your life, from your feelings and moods to your ability to maintain relationships.
If you’ve already been prescribed antidepressants, make sure to follow the directions provided by your healthcare provider. If your medication still doesn’t work after several weeks, reach out to your provider and let them know.
If you’re feeling depressed, you can connect with a licensed mental health provider using our online psychiatry service. If appropriate, you’ll receive evidence-based medicine and expert help for your depression or anxiety.
You can also learn more about dealing with depression, anxiety and other mental health issues using our free mental health resources.
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