Interaction Details

There were no interactions found between Promethazine and Comfrey. This does not mean the potential for an interaction does not exist, however. There is often a lack of studies and data surrounding traditional medicine, especially concerning drug interactions, so it is important to always consult your provider before making any changes to your medication regimen.


Still looking for more information about combining Promethazine and Comfrey? Ask Dr. Brian Staiger about it by contacting him directly.

Comfrey Overview

Comfrey Comfrey (Symphytum officinale) is an herbaceous plant that belongs to the borage family (Boraginaceae). It is native to Europe and Asia and is known for its hairy, green leaves and small, purple, bell-shaped flowers. Comfrey has a long history of use in traditional medicine and contains a number of active compounds, including allantoin, which is believed to have anti-inflammatory and healing properties. It has been traditionally used to treat a variety of ailments, including wounds, fractures, and skin conditions. In addition, comfrey is believed to have astringent and expectorant effects, and has been used to treat respiratory disorders and coughs. It is important to note that comfrey may cause liver damage if taken in large amounts (orally) or over a long period of time and should be used with caution. The FDA has recommended removal of oral comfrey products from the market due to potential for liver toxicity although it is currently still available. It is most often seen in topical forms (e.g., as an ointment).
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Promethazine Overview

  • Promethazine is used to relieve the symptoms of allergic reactions such as allergic rhinitis (runny nose and watery eyes caused by allergy to pollen, mold or dust), allergic conjunctivitis (red, watery eyes caused by allergies), allergic skin reactions, and allergic reactions to blood or plasma products. Promethazine is used with other medications to treat anaphylaxis (sudden, severe allergic reactions) and the symptoms of the common cold such as sneezing, cough, and runny nose. Promethazine is also used to relax and sedate patients before and after surgery, during labor, and at other times. Promethazine is also used to prevent and control nausea and vomiting that may occur after surgery, and with other medications to help relieve pain after surgery. Promethazine is also used to prevent and treat motion sickness. Promethazine helps control symptoms, but will not treat the cause of the symptoms or speed recovery. Promethazine is in a class of medications called phenothiazines. It works by blocking the action of a certain natural substance in the body.

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Comfrey - More Interactions

Comfrey interacts with 409 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.

Ask A Pharmacist About Your Herbal Questions!

Dr. Brian Staiger, PharmD

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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