Can Increasing Your Dose Of Prozac Cause Anxiety?
In our latest question and answer, the pharmacist discusses whether or not increasing your dose of Prozac can cause anxiety symptoms and how long you can expect them to last if they do occur.
I was increased on Prozac from 20 mg to 30 mg a week ago and I have felt more anxiety as a result. My doctor says it’s breakthrough symptoms, not the Prozac. How long do breakthrough symptoms last?
Oct 07, 2022- Increasing your Prozac dose may temporarily cause anxiety similar to what you experienced when first starting the medication, but this side effect usually improves within 4-12 weeks. About 15% of patients experience worsening anxiety when starting or changing their SSRI dose, and these effects are typically milder than initial side effects since your body has already adjusted to the medication. If you didn't have anxiety when you first started Prozac, any anxiety you're experiencing now is likely related to life circumstances rather than the dose increase.
Answer
Hi Robin and thank you for your question. I’m glad that you turned to your physician to help manage your mental health. Occasionally, it’s necessary to change the dose of a medication, even if that same dose seemed to help better in the past.
Fluoxetine (or under the brand Prozac) was the first selective serotonin reuptake inhibitor approved for use over 30 years ago, so we have decades of research and outcomes that we can look to.
When it comes to fluoxetine, most side effects tend to occur when the medication is started for the first time.
Generally, these side effects gradually resolve and you’ll start to experience the positive antidepressant effects of the medication after being on the medication for 4-12 weeks.
Dose Increases Can Cause A Temporary Increase In Side Effects
Typically, if you increase the dose of the medication, you may experience similar side effects as when you first started the medication. These are usually milder since you have probably been on the medication for a while at this point.
Research suggests that about 15% of patients starting or changing their SSRI dose do experience a worsening amount of anxiety that generally improves after 4-12 weeks of therapy. When you first started taking fluoxetine, did you experience anxiety? If so, you’ll probably see this anxiety resolve over the course of the next few weeks. If you didn’t, then it is probably related to life circumstances or your condition, and not the medication.
When it comes to SSRIs, the best advice that I can give any patient starting or changing their dose is patience!
If your breakthrough anxiety that you are experiencing is due to life circumstances, the fluoxetine will help, but it might take another month or two. In that time, I hope that your life situation improves. Good luck, and just remember that the medication is effective, it just takes a while to help.
Final Words
Thanks for reaching out to us Robin and if anything else comes up, please reach out.
References & sources
- Fluoxetine Monograph — PubChem
- What are the clinical implications of new onset or worsening anxiety during the first two weeks of SSRI treatment for depression? — Wiley Online Library
Glossary — Terms in This Answer
- Fluoxetine
- A medication used to treat depression and anxiety that works by affecting serotonin levels in the brain.
- Selective serotonin reuptake inhibitor
- A type of antidepressant medication that increases serotonin in the brain by preventing its reabsorption.
- SSRI
- Short for selective serotonin reuptake inhibitor, a common class of antidepressant drugs.
- Antidepressant
- A medication prescribed to treat depression by affecting brain chemicals related to mood.
- Side effects
- Unwanted or unpleasant reactions that can occur when taking a medication.
- Dose
- The specific amount of a medication that a person takes at one time or regularly.
- Breakthrough anxiety
- Anxiety symptoms that occur despite taking medication meant to manage anxiety.
Dr. Brian Staiger, PharmD
Doctor of Pharmacy, board certified clinical pharmacist (BCPS), American Herbalist Guild, Medication Therapy Management certified
Brian Staiger, PharmD, BCPS, is a licensed pharmacist with more than 13 years of experience across retail pharmacy, clinical pharmacy, medication safety, pharmacy program development, and healthcare administration. He is the founder of HelloPharmacist.com, where he helps patients...
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