Pelargonium sidoides (Umckaloabo), a herbal remedy, for treating acute respiratory tract infections

Umckaloabo is a herbal extract derived from the plant Pelargonium sidoides (P. sidoides) and is available in both tablet and liquid forms. The extract is used for the treatment of acute respiratory tract infections (ARIs) where antibiotic use is unnecessary. In the light of inappropriate antibiotic use and increasing drug resistance rates worldwide, the need for an alternative, effective remedy for these medical conditions is crucial. On the other hand, there are concerns as to the safety of Umckaloabo.

We reviewed 10 randomized clinical trials of which eight were of sufficient quality for inclusion into the analyses. Three trials dealt with acute bronchitis in adults and showed inconsistent but overall positive results for resolution of symptoms (all symptoms, cough and sputum production). For acute bronchitis in children, there were also three studies showing an inconsistent but overall positive combined effect. The available data indicate that the tablet form may be less effective compared to the alcoholic extract. However, the number of trials is not sufficient to prove this. One study each was available for the treatment of acute sinusitis and the common cold in adults. Both showed that the drug was effective in resolving all symptoms including headaches and nasal discharge when taken for an extended time period. Adverse events were more common with P. sidoides, but none were severe.

Overall we considered the quality of the evidence low or very low for all major outcomes as there were few studies per disease entity, and all were from the same investigator (the manufacturer) and performed in the same region (Ukraine and Russia). Thus, in summary, there is limited evidence for the effectiveness of P. sidoides in the treatment of ARIs. The evidence is up to date as of April 2013.

Authors' conclusions: 

P. sidoides may be effective in alleviating symptoms of acute rhinosinusitis and the common cold in adults, but doubt exists. It may be effective in relieving symptoms in acute bronchitis in adults and children, and sinusitis in adults. The overall quality of the evidence was considered low for main outcomes in acute bronchitis in children and adults, and very low for acute sinusitis and the common cold. Reliable data on treatment for other ARIs were not identified.

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Pelargonium sidoides (P. sidoides), also known as Umckaloabo, is a herbal remedy thought to be effective in the treatment of acute respiratory infections (ARIs).


To assess the efficacy and safety of P. sidoides for the treatment of ARIs in children and adults.

Search strategy: 

In April 2013 we searched MEDLINE, Journals@Ovid, The Cochrane Library, Biosis Previews, Web of Science, CINAHL, CCMed, XToxline, Global Health, AMED, Derwent Drug File and Backfile, IPA, ISTPB + ISTP/ISSHP, EMBASE, Cambase, LILACS, PubMed component “Supplied by Publisher”, TRIPdatabase, the publisher databases: Deutsches Ärzteblatt, Thieme, Springer, ScienceDirect from Elsevier. We conducted a cited reference search (forward) in Web of Science of relevant papers for inclusion. In addition we searched the study registries, Deutsches Register klinischer Studien DRKS (German Clinical Trials Register), International Clinical Trials Registry Platform (ICTRP) – WHO ICTRP, Current Controlled Trials and EU Clinical Trials Register.

Selection criteria: 

Double-blind, randomized controlled trials (RCTs) examining the efficacy of P. sidoides preparations in ARIs compared to placebo or any other treatment. Complete resolution of all symptoms was defined as the primary outcome; in addition, we examined resolution of predefined key symptoms.

Data collection and analysis: 

At least two review authors (AT, JG, WK) independently extracted and quality scored the data. We performed separate analyses by age group and disease entity. Subanalysis considered type of preparation (liquid, tablets). We examined heterogeneity using the I2 statistic. We calculated pooled risk ratios (RR) using a fixed-effect model if heterogeneity was absent (I2 < 5%; P > 0.1), or a random-effects model in the presence of heterogeneity. If heterogeneity was substantial (I2 > 50%; P < 0.10), a pooled effect was not calculated.

Main results: 

Of 10 eligible studies eight were included in the analyses; two were of insufficient quality. Three trials (746 patients, low quality of evidence) of efficacy in acute bronchitis in adults showed effectiveness for most outcomes in the liquid preparation but not for tablets. Three other trials (819 children, low quality of evidence) showed similar results for acute bronchitis in children. For both meta-analyses, we did not pool subtotals due to relevant heterogeneity induced by type of preparation.

One study in patients with sinusitis (n = 103 adults, very low quality of evidence) showed significant treatment effects (complete resolution at day 21; RR 0.43, 95% confidence interval (CI) 0.30 to 0.62). One study in the common cold demonstrated efficacy after 10 days, but not five days (very low quality of evidence). We rated the study quality as moderate for all studies (unvalidated outcome assessment, minor attrition problems, investigator-initiated trials only). Based on the funnel plot there was suspicion of publication bias.

There were no valid data for the treatment of other acute respiratory tract infections. Adverse events were more common with P. sidoides, but none were serious.