title: Efficacy of a comfrey root extract ointment in comparison to a diclofenac gel in the treatment of ankle distortions: results of an observer-blind, randomized, multicenter study.
abstract: In the treatment of minor blunt injuries several topical drugs are known to have anti-inflammatory and analgesic properties. They represent, however, two fundamentally different major pharmacological therapy approaches: the "chemical-synthetical" and the "phytotherapeutical" approach. The main objective of this trial (CODEC_2004) was to compare the efficacy and tolerability of an ointment of Comfrey extract (Extr. Rad. Symphyti) with that of a Diclofenac gel in the treatment of acute unilateral ankle sprain (distortion). In a single-blind, controlled, randomized, parallel-group, multicenter and confirmatory clinical trial outpatients with acute unilateral ankle sprains (n=164, mean age 29.0 years, 47.6% female) received either a 6 cm long ointment layer of Kytta-Salbe f (Comfrey extract) (n=82) or of Diclofenac gel containing 1.16 g of diclofenac diethylamine salt (n=82) for 7 +/- 1 days, four times a day. Primary variable was the area-under-the-curve (AUC) of the pain reaction to pressure on the injured area measured by a calibrated caliper (tonometer). Secondary variables were the circumference of the joint (swelling; figure-of-eight method), the individual spontaneous pain sensation at rest and at movement according to a Visual Analogue Scale (VAS), the judgment of impaired movements of the injured joint by the method of "neutral-zero", consumption of rescue medication (paracetamol), as well as the global efficacy evaluation and the global assessment of tolerability (both by physician and patient, 4 ranks). In this study the primary variable was also to be validated prospectively. It was confirmatorily shown that Comfrey extract is non-inferior to diclofenac. The 95% confidence interval for the AUC (Comfrey extract minus Diclofenac gel) was 19.01-103.09h*N/cm2 and was completely above the margin of non-inferiority. Moreover, the results of the primary and secondary variables indicate that Comfrey extract may be superior to Diclofenac gel.
authors.affiliation: Merck Selbstmedikation GmbH, Roesslerstr. 96, D-64293 Darmstadt, Germany.
authors.forename: H G
authors.initials: HG
authors.lastname: Predel
authors.forename: B
authors.initials: B
authors.lastname: Giannetti
authors.forename: R
authors.initials: R
authors.lastname: Koll
authors.forename: M
authors.initials: M
authors.lastname: Bulitta
authors.forename: C
authors.initials: C
authors.lastname: Staiger
mesh_terms: D000293:Adolescent; D000328:Adult; D016512:Ankle Injuries / Q000188:drug therapy*; D019540:Area Under Curve; D020844:Comfrey; D004008:Diclofenac / Q000627:therapeutic use*; D005260:Female; D005782:Gels; D006801:Humans; D008297:Male; D008875:Middle Aged; D009824:Ointments; D010147:Pain Measurement; D008517:Phytotherapy / Q000009:adverse effects; D010936:Plant Extracts / Q000009:adverse effects / Q000627:therapeutic use*; D028321:Plant Preparations; D018517:Plant Roots; D016037:Single-Blind Method; D013180:Sprains and Strains / Q000188:drug therapy*; D016896:Treatment Outcome
chemical_list: D005782:Gels; D009824:Ointments; D010936:Plant Extracts; D028321:Plant Preparations; D004008:Diclofenac