Why does Cymbalta take so long to work? (+3 factors)

In this article, we will discuss why Cymbalta takes time to start working. We will also discuss what factors may influence the onset of the effect of this medication and what to do if you do not get the desired effects.

Why does Cymbalta take so long to work?

Cymbalta (Duloxetine) takes time to work because it exerts its effects by gradually adjusting the neurotransmitter levels in your brain.

Antidepressants like Cymbalta alter the level of excitatory neurotransmitters in your brain and this process can take time. Not only this but your body takes time to adjust to this change and to actually start responding to the medication.

However, people respond differently to medications, especially those meds which alter the brain chemistry. So some people may begin to feel the beneficial effects of Cymbalta earlier than others.

Cymbalta usually takes 8-12 weeks to exert its full effects. If it does not achieve your desired therapeutic response, reach out to your healthcare provider for personalized guidance.

How does Cymbalta work in the body?

Cymbalta is a serotonin noradrenaline reuptake inhibitor (SNRI) that slowly increases the amount of neurotransmitters (serotonin and norepinephrine) in your brain which is responsible for modulating mood, learning, memory and other physiological processes (1).

Depression and other mental illnesses usually progress slowly and you can’t expect your antidepressant to treat it overnight. You need to be consistent in taking your antidepressant for a month or two to be certain whether or not the medication manages your symptoms adequately.

It is important to make sure that you don’t leave your treatment halfway and give your antidepressant enough time to take effect.

Cymbalta manages the symptoms associated with depression like sadness and crying etc. It can also help with anxiety and depression associated with fibromyalgia and neuropathy (2).

What factors affect the time taken by Cymbalta to work?

Factors affecting the time taken by Cymbalta to work include:


The prescribed dosage plays an important role, as higher dosages may yield faster results but also increase the likelihood of adverse effects. It is crucial to adhere to the prescribed dosage and refrain from adjusting it without medical guidance.

Individual differences

Individual differences in the metabolism of each person impact how quickly the body processes and responds to the medication. Each person’s body processes medications differently. Some individuals may metabolise Cymbalta more quickly or slowly, affecting how soon it reaches therapeutic levels in the body.

Condition for which Cymbalta is prescribed

The condition being treated plays a role in how quickly Cymbalta works such as it might take longer to notice improvements in chronic conditions like GAD or fibromyalgia as compared to acute conditions like certain types of pain.

Drug interaction

Drug interactions can affect how quickly Cymbalta starts working. Certain medications or substances can enhance or inhibit its effects, affecting its onset of action.

What if Cymbalta does not work for you?

If you don’t feel any improvement in your symptoms, just wait for some time and observe your overall condition before switching to a different antidepressant.

Antidepressant is a trial-based therapy, as it involves trying different medications because not all of them are well-tolerated by everyone. However, if there is still no improvement after 2-3 months, you should inform your doctor.

There are different antidepressants that can be used instead of Cymbalta. However, it is best to give your body time to adjust to the medication, if it does not cause unbearable side effects.

Some side effects usually occur with almost every other antidepressant during the early course of treatment, such as nausea, vomiting, diarrhoea, sweating etc, and you should not worry about them. Most of these side effects begin to subside within a few weeks as your body adjusts to the medication (3).

If Cymbalta still fails to manage your symptoms even after 2-3 months or causes side effects that make it extremely difficult for you to continue this medication, your doctor may switch you to a different antidepressant after safely tapering off the previous one.

Always remember, not to stop using antidepressants on your own as they can cause horrible withdrawal symptoms further worsening your condition (4).

In my view, Cymbalta takes time to show noticeable effects due to its mechanism of action. You may experience some early side effects during the first few weeks, but they soon disappear as your body adjusts to the medication.

Determining the best antidepressant is a trial-and-error process and you may need to try several antidepressants to find the one that suits you and your symptoms best. Just make sure you always follow your doctor’s guidance to ensure safe and effective use of the medication.


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