Whey Protein - Metronidazole, Tetracyline, Bismuth Subcitrate Potassium Interaction
Herbal: Whey Protein
Also Known As: MBP, Milk Protein, Milk Protein Isolate, Protéine de Lactosérum, Protéine de Lait, Whey, Whey Fraction, Whey Peptides, Whey Protein Concentrate, Whey Protein Hydrolysate, Whey Protein Isolate, WPC, WPI
Drug: Metronidazole, Tetracyline, Bismuth Subcitrate Potassium
Brand names:
Pylera
Medical Content Editor Dr. Brian Staiger, PharmD
Last updated
May 04, 2025
Interaction Details
Metronidazole, Tetracyline, Bismuth Subcitrate Potassium is classified as belonging to the following category: Tetracycline Antibiotics
Theoretically, whey protein might decrease tetracycline absorption.
Whey protein contains minerals, such as calcium, that bind to tetracyclines in the gut. To avoid this interaction, advise patients to take oral tetracyclines at least 2 hours before or 4-6 hours after whey protein.
Interaction Rating
Likelihood of Occurrence
ProbableInteraction has not been documented in well-controlled studies, however, the interaction has been demonstrated in some small human studies or in controlled animal studies in conjunction with multiple case reports.
References
- Martindale W. Martindale the Extra Pharmacopoeia. Pharmaceutical Press, 1999.
- Maton PN, Burton ME. Antacids revisited: a review of their clinical pharmacology and recommended therapeutic use. Drugs 1999;57:855-70.
Whey Protein Overview
Whey protein is a type of protein derived from cow's milk. Specifically, whey comes from the cheesemaking process. Enzymes are added to milk, which separates the milk into cheese curds and liquid whey. Whey is a complete protein, meaning that it contains all nine essential amino acids that the body needs but cannot produce on its own. Whey protein is often used as a supplement to help build and repair muscle tissue, and it is popular among athletes and bodybuilders.
There are three main types of whey protein: concentrate, isolate, and hydrolysate. The concentrate contains a higher amount of lactose (milk sugar) and fat, while isolate is a purer form of protein that contains less lactose and fat. Hydrolysate is a predigested form of whey protein that is easier for the body to absorb.
Whey protein is often consumed in the form of powders, shakes, and bars, and it can be mixed with water, milk, or other beverages.
Drug interactions with whey protein typically result due to the calcium content of whey, which can decrease absorption of some drugs, including many classes of antibiotics.
Metronidazole, Tetracyline, Bismuth Subcitrate Potassium Overview
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Bismuth, metronidazole, and tetracycline is used along with other ulcer medications to treat duodenal ulcers. It is in a class of medications called antibacterial agents. It works by preventing the growth and spread of Helicobacter pylori bacteria, which often occurs with ulcers. Treating this infection keeps ulcers from coming back.
Whey Protein - More Interactions
Whey Protein interacts with 52 drugs
Interaction Rating Key
These severity listings are for informational use only. Never start, stop or otherwise change your therapy before speaking with your provider.
| Major | The combined use of these agents is strongly discouraged as serious side effects or other negative outcomes could occur. |
| Moderate | Use cautiously under the care of a healthcare professional or avoid this combination. A significant interaction or negative outcome could occur. |
| Minor | Be aware that there is a chance of an interaction. Watch for warning signs of a potential interaction. |
| Unknown | No interactions have been reported or no interaction data is currently available. |
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Parts of this content are provided by the Therapeutic Research Center, LLC.
DISCLAIMER: Currently this does not check for drug-drug interactions. This is not an all-inclusive comprehensive list of potential interactions and is for informational purposes only. Not all interactions are known or well-reported in the scientific literature, and new interactions are continually being reported. Input is needed from a qualified healthcare provider including a pharmacist before starting any therapy. Application of clinical judgment is necessary.
© 2021 Therapeutic Research Center, LLC
Drug descriptions are provided by MedlinePlus.
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In addition to being a clinical pharmacist specializing in pharmacotherapy, Dr. Brian Staiger is a registered herbalist through the American Herbalist Guild. He has combined his passion for pharmacy practice with the study of medical ethnobotany to improve patient care. Feel free to reach out about any of your herbal or medication questions!
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