Summary of results for complementary and alternative medicine (CAM) tested in single trials
| CAM | Intervention group | Control group | Treatment duration | Outcome | First author [ref.] | Country |
| Curcumin | “Standard” asthma treatment + 500 mg curcumin twice daily | “Standard” asthma treatment | 4 weeks | Difference (+): pre/post-bronchodilator FEV1 No difference (−): clinical symptom severity, adverse events | Abidi [11] | India |
| New Zealand green-lipped mussel | Two 150 mg capsules of New Zealand green-lipped mussel twice daily | Two 150 mg placebo capsules twice daily | 8 weeks | Difference (+): mean daytime wheeze, mean morning PEFR No difference (−): nocturnal awakening, use of short-acting inhaled β2-agonists, mean FEV1, evening PEFR | Emelyanov [12] | Russia |
| Solanum xanthocarpum | Solanum xanthocarpum 300 mg orally once daily | Salbutamol 4 mg once daily or deriphylline 220 mg | 1 day | Difference (+): FVC, FEV1, PEFR No difference (−): none | Govindan [13] | India |
| Solanum trilobatum | Solanum trilobatum 300 mg orally once daily | Salbutamol 4 mg once daily or deriphylline 220 mg | 1 day | Difference (+): none No difference (−): FVC, FEV1, PEFR | Govindan [13] | India |
| Coenzyme Q10 | 120 mg Coenzyme Q10 + 400 mg α-tocopherol + 250 mg vitamin C + “standard” asthma treatment | “Standard” asthma treatment | 32 weeks (16-week crossover) | Difference (+): total usage of corticosteroids No difference (−): FEV1, FEV1/FVC, PEFR | Gvozdjakova [14] | Slovakia |
| Selenium | Daily oral 100 μg sodium selenite | Daily oral placebo | 14 weeks | Difference (+): none No difference (−): FEV1, PEFR | Hasselmark [15] | Sweden |
| Auranofin | 3 mg oral auranofin twice daily | 3 mg oral placebo twice daily | 12 weeks | Difference (+): none No difference (−): FEV1, FVC | Honma [16] | Japan |
| Pyridoxine (vitamin B6) | 300 mg oral pyridoxine (mixed with lactose) daily + oral prednisolone | Oral placebo daily + oral prednisolone | 9 weeks | Difference (+): none No difference (−): morning/evening PEFR, FEV1, morning/evening symptom scores, nocturnal asthma awakening | Kaslow [17] | USA |
| Aqueous extract of propolis | 13% aqueous extract of propolis in water orally once daily + oral theophylline | Placebo sachet in water orally once daily + oral theophylline | 8 weeks | Difference (+): need for rescue medication, number of nocturnal attacks per week, FVC, FEV1, PEFR No difference (−): none | Khayyal [18] | Egypt |
| Vitamin E | Two capsules (250 mg vitamin E + soya bean oil) | Two placebo capsules (gelatine base) | 6 weeks | Difference (+): none No difference (−): FEV1, FVC, mean morning peak flow, symptom score, bronchodilator use | Pearson [19] | UK |
| AKL1# | Two AKL1 capsules twice daily | Two placebo capsules twice daily | 36 weeks | Difference (+): none No difference (−): PEFR, FEV1, AQLQ, ACQ, LCQ | Thomas [20] | UK |
| Lactose powder | 6.25 mg, 12.5 mg, 25 mg, 50 mg or 100 mg of lactose powder in rotadisk | Inhaled placebo in rotadisk | 1 day | Difference (+): none No difference (−): FEV1 | Thoren [21] | Sweden |
| TJ-96 | 2.5 g of oral Saiboku-to TJ-96 three times daily | Oral placebo three times daily | 8 weeks | Difference (+): symptom score No difference (−): FEV1 | Urata [22] | Japan |
| Pingchuan Yiqi Granule | Two oral Pingchuan Yiqi Granule capsules three times daily | Four oral Ruyi Dingchuan pills three times daily | 1 week | Difference (+): none No difference (−): FEV1, PEFR | Zhang [23] | China |
FEV1: forced expiratory volume in 1 s; PEFR: peak expiratory flow rate; FVC: forced vital capacity; AQLQ: Asthma Quality of Life Questionnaire; ACQ: Asthma Control Questionnaire; LCQ: Leicester Cough Questionnaire. #: Picrorrhiza kurroa, Zingiber officinale, Ginkgo biloba and apocynin.