Table 3

Description of trials included in this review

Study

Sample Size

Condition; mean age (range)

Harpagophytum Intervention / control

Outcome measures and effects

Adverse effects

Reviewer's Overall Conclusions

Schrüffler 1980 (Germany)

50

Osteoarthritis; 51 years

2500 mg/ day, (harpagoside less than 30 mg per day) / Phenylbutazone for 4 weeks

mean pain improvements: H 80%, Phenylbutazone 72%; physical impairment: H n = 1, Phenybutazone n = 5; morning stiffness: H n = 2, Phenybutazone n = 5

0 H vs 4 Phenylbutazone

H better than Phenylbutazone

Lecomte and Costa 1992 (France)

89

Osteoarthritis; (55–75) years

2000 mg/day (Harpagoside content estimated indirectly as 60 mg per day) / placebo for 60 days

mean pain improvement: H 38%, P 25% p < .05; finger-ground distance modified Schober test (cm) mean improvement: H 16%, P 6% p < .05

none for either group

H better than placebo

Biller 2002 (Germany)

78

Osteoarthritis; not stated

4500 mg/day, (harpagoside content estimated at < 30 mg per day) / placebo for 20 weeks

responders: H 90%, P 80% p-value not stated; mean consumption of ibuprofen: H .1, P .5 tablets

not stated

H better than placebo

Chantre et al. 2000 (France)

122

Osteoarthritis; 62 years

4500 mg / day, (57 mg harpagoside per day) / Diacerhein for 16 weeks

difference after 16 weeks between groups as measured by Lequesne functional index: less than 10 mm NS (intention-to-treat analysis with not all possible confounders considered)

10 H vs 21 Diacerhein

H not worse than diacerhein

Frerick et al. 2001 (Germany)

46

Osteoarthritis; 59 years

4500 mg/day, (< 30 mg harpagoside per day) / placebo for 20 weeks

responders: H 71%, P 41% p=.041; WOMAC component pain NS (type of statistical analysis not stated)

8 H vs 7 P

H better than placebo

Chrubasik et al. 1996b (Germany)

118

Back pain; 54 years

4500 mg/day, (50 mg harpagoside per day) / placebo for 4 weeks

mean tramadol consumption: H 99 ± 157 mg, P 102 ± 250 mg p =.44; number of pain-free patients at 4th week: H 9 P 1 p=.008; percentage change Arhus component pain: H 34%, P 6% p=.016 (per protocol analysis)

4 H vs 10 P

not on primary outcome measure

Chrubasik et al. 1997 (Germany)

102

Back pain; 49 years

4500 mg/day, (30 mg harpagoside per day) / conventionally treating physicians administering oral NSAIDs, physical exercises, or paravertaebral injections for 6 weeks

number of pain-free patients 4th week: H 16, C12 NS; number of pain free patients 6th week: H 20, C 23 NS; percentage change Arhus component pain after four weeks: H 23%, C 22% p=.95; after 6 weeks H 33%, C 38% p=.38

5 H vs 0 C

H not worse than C

Chrubasik et al. 1999 (Germany)

197

Back pain; 56 years

4500 and 9000 mg/day, (50 and 100 mg harpagoside per day) / placebo for 4 weeks

number of pain-free patients: H-100 18%, H-50 9%, P 5% p=.027); percentage change Arhus component pain: H-100 vs H-50 vs P NS (intention-to-treat analysis)

10 P, 18 H-50, 17 H-100

H better than placebo

Chrubasik et al. 2003a (Germany)

88

Back pain; 62 years

4500 mg/day, (60 mg harpagoside per day) / Rofecoxib for 6 weeks

number of pain-free patients: H 22%, Rofecoxib 11% NS; percentage change Arhus component pain: H 30%, Rofecoxib 29% (intention-to-treat analysis)

14 H, 14 Rofecoxib

H not worse than Rofecoxib

Schmelz and Hämmerle 1999 (Germany)

100

Mixed pain; not stated

4500 mg/day, (30 mg harpagoside per day) / placebo for 30 days

free of low back pain: H n = 4, P n = 2; free of other pain: H n = 5, P n = 0 (confounders not considered)

not stated

H better than placebo

Guyader 1984 (France)

50

Mixed pain; 64 years

Harpagoside content estimated indirectly as <20 mg harpagoside per day / placebo for 1–3 'cycles' of 21 days each

mean pain improvements: H 72%, P 65% (confounders not considered)

6 H vs 3 P

H better than placebo

Goebel et al. 2001 (Germany)

65

Mixed pain; 28 years

4500 mg/day, (< 30 mg harpagoside per day) / placebo for 28 days

4 H vs 2 P

H better than placebo

Key: NS = not significant; H = harpagophytum; P = placebo; WOMAC = Western Ontario and McMaster Universities Arthritis Index

Gagnier et al. BMC Complementary and Alternative Medicine 2004 4:13   doi:10.1186/1472-6882-4-13