The combination of hawthorn extract and camphor significantly increases blood pressure: A meta-analysis and systematic review

Background: A fixed combination of hawthorn and camphor (Korodin Herz-Kreislauf-Tropfen^®) has been used in the therapy of hypotension for decades. Although its efficacy was evaluated in clinical trials, these studies have not been critically assessed in meta-analyses.

Purpose: To systematically evaluate the efficacy of a fix combination of camphor and hawthorn extract (Korodin^®) on blood pressure and cognition compared to placebo, in a meta-analysis based on randomized controlled trials (RCTs).

Study design: The meta-analysis was carried out following the PRISMA guidelines, using the PICO format, and it was registered in the PROSPERO register.

Methods: The Cochrane Central Register of Controlled Trials, PubMed, Embase, and Web of Science databases were searched for relevant studies. Placebo-controlled clinical studies involving adult patients receiving a fix combination of hawthorn extract and camphor were included. No language or publication year restrictions were applied.

Results: Four randomized trials including a total of 221 patients were pooled for statistical analysis. According to the present meta-analysis, the fixed combination of hawthorn and camphor significantly increases systolic and diastolic blood pressure compared to placebo (p-values: 0.017 and 0.049, respectively) and had a beneficial, but not statistically significant effect on the cognitive performance in the connect-the-numbers test (p-value: 0.071).

Conclusion: Korodin^® is an effective and presumably safe complementary therapy for the treatment of hypotension. Its blood pressure increasing effect is confirmed; however, the evidence supporting its use is very limited. The optimum dose and duration of treatment is still unclear. The comprehensive evaluation of efficacy and safety is required in further, high-quality clinical studies, involving larger patient populations and comparable endpoints.