Last update Jan. 7, 2022

Fenfluramine Hydrochloride

High Risk

Poorly safe. Evaluate carefully. Use safer alternative or interrupt breastfeeding 3 to 7 T ½ (elimination half-lives). Read the Comment.

Amphetamine-related sympathomimetic used in the treatment of obesity. It is also used in certain serious drug-resistant epilepsies. (FDA 2020)

Since the last update we have not found any published data on its excretion in breast milk.

Its pharmacokinetic data (low molecular weight and low percentage of plasma protein binding) makes it likely that significant amounts will pass into breast milk.

Due to its frequent and serious cardiovascular toxicity it has been withdrawn as an anorectic from the market in most countries of the world.(FDA 2020, Kakkar 2015, Li 2011, AEMPS 2000)

Breastfeeding women return to pre-pregnancy body weight sooner than bottle-feeding mothers.

See below the information of this related product:

  • Dexfenfluramine Hydrochloride ( Poorly safe. Evaluate carefully. Use safer alternative or interrupt breastfeeding 3 to 7 T ½ (elimination half-lives). Read the Comment.)


  • Hypocaloric Diet ( Safe. Compatible. Minimal risk for breastfeeding and infant.)
  • Maternal Sport ( Safe. Compatible. Minimal risk for breastfeeding and infant.)
  • Orlistat (Moderately safe. Probably compatible. Mild risk possible. Follow up recommended. Read the Comment.)

Suggestions made at e-lactancia are done by APILAM team of health professionals, and are based on updated scientific publications. It is not intended to replace the relationship you have with your doctor but to compound it.

Jose Maria Paricio, Founder & President of APILAM/e-Lactancia

Your contribution is essential for this service to continue to exist. We need the generosity of people like you who believe in the benefits of breastfeeding.

Thank you for helping to protect and promote breastfeeding.

José María Paricio, founder of e-lactancia.

Other names

Fenfluramine Hydrochloride in other languages or writings:


Fenfluramine Hydrochloride belongs to this group or family:


Main tradenames from several countries containing Fenfluramine Hydrochloride in its composition:


Variable Value Unit
Oral Bioavail. 70 %
Molecular weight 268 daltons
Protein Binding 34 %
VD 11.9 l/Kg
Tmax 4 - 5 hours
20 hours


  1. FDA. Fenfluramine (Fintepla). Drug Summary. 2020 Full text (in our servers)
  2. Kakkar AK, Dahiya N. Drug treatment of obesity: current status and future prospects. Eur J Intern Med. 2015 Mar;26(2):89-94. Abstract
  3. Li MF, Cheung BM. Rise and fall of anti-obesity drugs. World J Diabetes. 2011 Feb 15;2(2):19-23. Abstract
  4. AEMPS Retirada del mercado de los medicamentos anorexígenos de acción central. 2000 Full text (in our servers)

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