A Comprehensive Review of Herbal Supplements Used for Persistent Symptoms Attributed to Lyme Disease.

CONTEXT: Lyme disease is the most common, tick-borne disease in the USA. While most patients successfully recover with antibiotics, some patients experience persistent symptoms for months to years. Patients who attribute chronic symptoms to Lyme disease commonly use herbal supplements. The complexity, variability in dose and formulation, and lack of data for these herbal compounds make it difficult to assess their efficacy and safety.

OBJECTIVE: This review examines the evidence for the antimicrobial activity, safety, and drug-drug interactions of 18 herbal supplements that patients commonly use for treatment of persistent symptoms attributed to Lyme disease.

DESIGN: The research team performed a narrative review by searching the PubMed, Embase, Scopus, Natural Medicines databases, and NCCIH website. The search used the keywords for 18 herbal compounds: (1) andrographis (Andrographis paniculate), (2) astragalus (Astragalus propinquus), (3) berberine, (4) cat's claw bark (Uncaria tomentosa), (5) cordyceps (Cordyceps sinensis), (6) cryptolepis (Cryptolepis sanguinolenta), (7) Chinese skullcap (Scutellaria baicalensis), (8) garlic (Allium sativum), (9) Japanese knotwood (Polygonum cuspidatum), (10) reishi mushrooms (Ganoderma lucidum), (11) sarsaparilla (Smilax medica), (12) Siberian ginseng (Eleutherococcus senticosus), (13) sweet wormwood (Artemisia annua), (14) teasle root (Dipsacus fullonum), (15) lemon balm (Melissa officinalis), (16) oil of oregano (Origanum vulgare), (17) peppermint (Mentha x piperita), and (18) thyme (Thymus vulgaris). The team also searched for terms related to protocols, including Dr. Rawls' protocol and the Buhner protocol.

SETTING: University of Maryland Medical Center, Baltimore MD.

RESULTS: Seven of the 18 herbs reviewed had evidence for in-vitro activity against B. burgdorferi . These compounds included: (1) cat's claw (2) cryptolepis, (3) Chinese skullcap, (4) Japanese knotweed, (5) sweet wormwood, (6) thyme, and (7) oil of oregano. With the exception of oil of oregano these compounds also have anti-inflammatory activity. In vivo data and clinical trials are lacking. Clinicians should be cautious as many of the identified compounds have drug interactions and additive effects that could lead to increased risks for bleeding, hypotension, and hypoglycemia.

CONCLUSIONS: Many of the herbs that alternative and integrative practitioners use to treat Lyme disease have anti-inflammatory effects that may contribute to patients' perceptions of symptomatic improvement. Some herbs have limited demonstrated anti-borrelial activity in vitro, but in-vivo data and clinical trial data is lacking. Further research is required to determine the efficacy, safety and appropriate use of these herbs for this patient population.