Progesterone and Phenobarbital Interaction
Drug interaction information between Progesterone and Phenobarbital.
Progesterone and Phenobarbital have a documented minor interaction in FDA labeling.
FDA drug labeling documents a minor-severity interaction between Progesterone and Phenobarbital. This page displays the available source-record category and label text. The category is not an individual risk estimate or medication-combination direction.
How They Interact
Phenobarbital makes your body break down progesterone faster than usual. This can make the progesterone treatment less effective.
FDA Label Information
Estradiol, Estrone Progesterone, and Other Steroidal Hormones Pretreatment with or concurrent administration of phenobarbital may decrease the effect of estradiol by increasing its metabolism.
Progesterone Also Interacts With
- Isotretinoin major
- Theophylline major
- Amoxicillin minor
- Amoxicillin/Clavulanate minor
- Medroxyprogesterone minor
Phenobarbital Also Interacts With
- Nirmatrelvir/Ritonavir major
- Ranolazine major
- Voriconazole major
- Canagliflozin moderate
- Cenobamate moderate
Frequently Asked Questions
What SPL severity band is on file for Progesterone + Phenobarbital?
Compiled FDA labeling labels this pair minor. That is a source-record field, not an individual medication-combination decision.
Which drug in this pair has the larger labeled-interaction portfolio?
Phenobarbital has 59 labeled pairs on file vs Progesterone's 7. In the minor band specifically: Progesterone has 5 (also Amoxicillin, Amoxicillin/Clavulanate, Medroxyprogesterone, Ziprasidone); Phenobarbital has 43 (also Estradiol, Doxycycline, Griseofulvin, Bazedoxifene).
What mechanism field is on file for Progesterone and Phenobarbital?
Phenobarbital makes your body break down progesterone faster than usual. This can make the progesterone treatment less effective.
Phenobarbital carries more major-labeled pairs than Progesterone
SPL source-record counts only. This page's band is minor · classes on file: Progesterone (Progestogen Hormone); Phenobarbital (Anticonvulsant (Barbiturate)).
Phenobarbital has 3 major-labeled pairs vs Progesterone's 2. This page itself is in the minor band, not the major band.
2 major · 0 moderate · 5 minor · 7 total
- Other minor peers for Progesterone
- Amoxicillin
- Amoxicillin/Clavulanate
- Medroxyprogesterone
- Ziprasidone
3 major · 13 moderate · 43 minor · 59 total
- Other minor peers for Phenobarbital
- Estradiol
- Doxycycline
- Griseofulvin
- Bazedoxifene
Sources: FDA Drug Labels (SPL) via openFDA (2026). This is for informational purposes only and is not medical advice. This registry does not provide individual medication-combination directions.
Read our methodology - how this data is sourced, computed, and verified.