An Evidence-Based Systematic Review of Echinacea (E. angustifolia DC, E. pallida, E. purpurea) by the Natural Standard Research Collaboration

Herb–drug interactions: an overview of systematic reviews

“…Our searches generated 4366 articles, of which 4320 had to be excluded (Figure 1). Thus 46 SRs met our inclusion criteria (Table 1) [9–54]. The following herbs were considered to interact with synthetic drugs: Aloe vera, Boswellia serrata, Calendula officinalis, Camellia sinensis, Cassia senna, Caulophyllum thalictroides, Cinnamomum spp.…”

“…The following drugs interacted with HMPs (Table 2): anaesthetics [16], anti‐arrhythmic agents [15, 27], antibiotics [19, 34, 36, 39, 40, 42, 46, 48, 49, 52, 53], anticoagulants [13, 15, 16, 18, 24, 26, 27, 29, 33, 34, 36, 37, 39, 40, 44–46, 49, 50, 52, 53], anticholinergics [17, 22], antidepressants [25, 26, 33, 45], antidiabetics [26, 27, 38, 40, 43, 47, 50–53], antihypertensives [16, 29, 33, 41, 43–46, 49, 53], anti‐inflammatory agents [13, 16, 35, 46, 52, 53], antimicrobials [31], antineoplastics [11, 14, 31, 36, 39–43, 51–53], antiplatelet agents [13, 15, 24, 25, 27, 29, 33, 34, 36, 37, 39, 40, 44, 45, 49, 50, 52, 53], anti‐epileptic drugs [13, 41, 45], antivirals [31, 40, 45, 51, 52], calcium channel blockers [24, 26, 30], cholesterol lowering agents [10, 13, 24, 26, 27, 40, 41, 44, 45, 50, 53], CYP‐450 metabolized agents [18, 21, 25, 29, 32, 34, 40, 42, 45, 48, 49, 53], diuretics [26, 30, 43], hormonal agents [18, 24, 26, 31, 40, 41, 43, 45, 49, 53, 54], hypoglycaemics [9, 10, 19, 20, 28], immunnosupressants [31, 34, 37, 40, 43, 46, 48] laxatives [27, 37, 50], leukotriene inhibitors [14], sedatives [12, 13, 23, 25, 45], selective serotonin re‐uptake inhibitors [23, 33] and vasolidators [30, 44].…”

“…These interactions were thought to cause a wide variety of clinical outcomes such as altered hormone concentrations [18], apraxia, death, haematoma, hyphaema, permanent neurological deficit [16], bradycardia and vasodilation [53], cardiovascular complications, hepatotoxicity [37], coma, sedation, lethargy, drowsiness [25], coronary vasoconstriction, tachycardia, diaphoresis, abdominal pain, muscle weakness [47], gastrointestinal upset [41], haemorrhage, bleeding [34], increased body weight, diarrhoea, decreased blood haemoglobin and altered calcium serum concentrations, hypoglycaemia [10, 38], increased liver enzyme levels [17], mania, headache, tremor and insomnia [26], microcytic anaemia, ischaemic stroke [45], organ fibrosis and death, cardiotoxicity, hypovolaemic shock, inflammatory reaction [43], potassium depletion, hypokalaemia [50], rhabdomyolysis, shock and death [42], severe intra‐operative and cerebral haemorrhage, hypertension, nausea or vomiting [49], transplant rejection, unwanted pregnancy, mania, orofacial dystonia, delayed emergence from anaesthesia, cardiovascular collapse [31].…”

Pharmacokinetic Herb-Drug Interactions (Part 2): Drug Interactions Involving Popular Botanical Dietary Supplements and Their Clinical Relevance

“…of the family Asteraceae are North American perennials whose roots and aerial parts have been used traditionally for a variety of medicinal purposes [15,16]. Echinacea formulations containing either root or whole plant extracts are marketed for their "immune stimulatory" properties and for prevention of the common cold [15,16]. Echinacea's popularity as an immune stimulator has placed it among the 10 topselling botanicals in the U. S. for many years.…”

“…While evidence from in vitro and animal studies lend credence to Echinacea preparations as immunomodulators, clinical findings remain equivocal. (For reviews of clinical efficacy see references [15][16][17][18][19].) The three species most commonly encountered are chemically dissimilar.…”