Comfrey root preparations are offered primarily in the form of ointments, pastes, creams and rubs in the group of anti-inflammatory agents and anti-rheumatics. Comfrey is also frequently included in ointments for the treatment of bruises, sprains and strains.
Since the mucilages it contains are good heat retainers, the pastes are well suited for making poultices and compresses. No tea preparations exist commercially.
Comfrey – the right dose
Unless otherwise prescribed, ointments and pastes should contain 5-20% of the dried drug.
A maximum amount of 100 μg of pyrrolizidine alkaloids including their N-oxides should be applied per day.
Comfrey: preparation
For purely external use, a decoction of comfrey root (1 part of the drug, 10 parts of water) can be prepared. 1 teaspoon is equal to about 4 g of the root.
Comfrey root should be stored in a dry place away from light.
When and how not to use comfrey
Because of the small amounts of pyrrolizidine alkaloids contained, comfrey root preparations should not be used during pregnancy, lactation, or by children under 2 years of age.
Commission E also recommends that comfrey root preparations be used only on intact skin. The duration of use, because of the pyrrolizidine alkaloids, should not exceed 4-6 weeks per year.
