Best Time Of Day To Take Prozac (Fluoxetine)

Is there a best time of day to take Prozac? I can't take it in the morning because that's when I take my thyroid medication.


Is there a best time of day to take Prozac? I can't take it in the morning because that's when I take my thyroid medication.

Asked by GHolt On Jun 10, 2022

Answered by
Medical Content Reviewed By HelloPharmacist Staff

Published Jun 10, 2022
Last updated Jun 07, 2023

Key points

  • Prozac (fluoxetine) is generally recommended to be taken in the morning, but can safely be taken at any time during the day.
  • The most important thing is to stay consistent with your dosing and take your medication at the same time every day.

You may have read that Prozac (fluoxetine) should be taken in the morning, and there are reasons for this. However, Prozac (fluoxetine) may be taken safely in the morning or evening with no difference in effectiveness.

The package insert for the medication does recommend morning dosing, as do most SSRI (Selective Serotonin Reuptake Inhibitor) medications. This is due to the typical side effects many people experience.

Two of the most common side effects to Prozac (fluoxetine) are insomnia and dry mouth.

Dry mouth tends to occur more often in the evening as our salivary glands are less active at night. Morning dosing can sometimes alleviate this. Insomnia tends to be less of an issue with morning dosing as well.

However, a small percentage of people do experience fatigue and drowsiness on Prozac (fluoxetine).

If this occurs, it is recommended to take the medication in the evening, about 1 to 2 hours before bedtime. In addition, due to conflicting medication administration schedules (like your current situation), it makes sense to take it in the evening.

As mentioned, there will be no difference in effectiveness, regardless of what time of day you take your dose. Just be sure to remain consistent. 


  • Prozac prescribing information, Lilly
  • Selective Serotonin Reuptake Inhibitors and Adverse Effects: A Narrative Review, PubMed

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