Magnolia Bark Extract

Scientific Name(s): Magnolia officinalis Rehd. et Wils.
Common Name(s): "Hu-bak", Magnolia bark

Medically reviewed by Drugs.com. Last updated on Jul 2, 2021.

Clinical Overview

Use

Most literature sources are from Japanese and Chinese foreign-language publications, clinical studies are on the efficacy of magnolia bark extract (MBE) are limited. Documentation on the materials and extracts for several studies is also limited. In vitro and animal studies document potential efficacy as an antibacterial, anti-inflammatory, and anticancer agent, as well as for use with Alzheimer disease, depression, diabetes, and menopause.

Dosing

MBE is commercially available in the United States and throughout Europe. Dosage varies depending on the condition treated, with weight loss products containing MBE available mostly in powder form. Several strengths are available for Relora, a patented blend marketed as "a natural stress management supplement" that includes MBE. Dosing recommendations include taking a 300 mg capsule of Relora 2 to 3 times per day. One small, randomized, controlled study treated patients with one 60 mg tablet of MBE daily to help relieve menopausal symptoms.

Contraindications

Avoid use if hypersensitivity exists for any of the components in MBE. No absolute contraindication could be found in the medical literature.

Pregnancy/Lactation

Avoid use during pregnancy and lactation because of limited clinical data. An animal study found that honokiol and magnolol blocked uterine contractions in rat uterus.

Interactions

Drug-herb interactions are documented, and caution is advisable in patients self-medicating with MBE. Magnolol may interact with acetaminophen. Additive adverse reactions with antiplatelet medications may occur in patients also self-medicating with magnolol. MBE and honokiol may interact with benzodiazepines. Magnolol may stimulate corticosterone secretion or increase steroid medication concentrations. MBE may cause excess sleepiness, vertigo, and dizziness in patients taking muscle relaxants.

Adverse Reactions

No dermatologic adverse effects were documented with topical application of magnolol and honokiol; however, several cases of allergic dermatitis have been documented in case reports. In one small clinical trial, a patient dropped out because of a number of adverse reactions, including heartburn, shaking hands, perilabial numbness, sexual dysfunction, and thyroid dysfunction.

Toxicology

Some sources document case reports of progressive interstitial renal fibrosis in patients consuming an herbal blend containing M. officinalis.

Scientific Family

• Magnoliaceae

Source

Numerous documented medicinal properties are associated with 2 major phenolic constituents, magnolol and honokiol, from the stem bark of M. officinalis Rehd. Et Wils.1, 2 Concentration variations of magnolol and honokiol exist in bark sourced from different provinces in China, as recorded in The Pharmacopoeia of the People's Republic of China. The plant is primarily indigenous to China and found at elevations of 200 to 3,000 meters.3

History

MBE has been used for over 1,000 years as a folk medicine in Asia.4, 5 In traditional Asian medicine, MBE has been prescribed for treating acute pain, headaches, diarrhea, allergies, asthma, and gynecological disorders. It has also been used to treat fever, anxiety, nervous disorders, depression, muscular pain, abdominal fullness, constipation, and thrombotic stroke.6,