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Table 2 Systematic reviews of clinical trials of hypericum and garlic preparations

From: Systematic reviews of complementary therapies – an annotated bibliography. Part 2: Herbal medicine

     

Features

  

Author

Indication

Intervention

Comparisons

Studies

1/2/3/

Results

Author's Conclusion

Year

    

4/5

  

St John's wort ( Hypericum perforatum )

Gaster

depression

hypericum

placebo and

8 RCT

p/y/p/

4 placebo-controlled trials with

Data suggest that hypericum is

2000 [20]

  

antidepressants

 

y/n

positive results, in 4 trials

superior to placebo, insuffcient

      

standard antidepr. tended to be

evidence re equivalence with

      

slightly better

antidepressants

Williams

depression

hypericum

placebo and

14 RCT

y/y/n/

Treatment response: RR 1.9

Data suggest that hypericum is

2000 &

 

(and other

antidepressants

 

y/y

(95%C11.2–2.8) vs. placebo and

superior to placebo, insuffcient

Mulrow 98

 

drugs)

   

1.2 (1.0–1.4) vs. antidepressants

evidence re equivalence with

[21, 22]

      

antidepressants

Kim 99 [23]

depression

hypericum

placebo and

6 RCT

p/y/y/

Treatment response: RR 1.48

Hypericum more effective than

   

antidepressants

 

y/y

(95%C11.03–1.92) vs. placebo

placebo and similarly effective as

      

and 0.98 (0.67–1.28) vs.

low dose antidepressants; quality

      

antidepressants

problems

Stevinson

depression

hypericum

placebo and

6 RCT

y/y/y/

Only trials published after Linde

Data confirm findings of earlier

99 [24]

  

antidepressants

 

y/n

96; trials show effects better

trials, but still insuff. evidence to

      

than placebo/similar to

assess equivalence with

      

antidepressants

antidepressants

Linde 98 &

depression

hypericum

placebo and

27 RCT

y/y/y/

Treatment response: RR 2.47

Hypericum more effective than

96 [25, 26]

  

antidepressants

 

y/y

(95%C11.69–3.61) vs. placebo

placebo. Inadequate evidence to

      

and 1.01 (0.87–1.16) vs.

assess equivalence with

      

antidepressants

antidepressants

Volz 97

depression

hypericum

placebo and

15

p/p/n/

Most placebo-controlled trials

A therapy with hypericum of mild

[27]

  

antidepressants

RCT/CCT

n/n

positive; similarly effective as

and moderate depression can be

      

(not adequately dosed)

attempted. Further studies needed

      

antidepressants

 

Ernst 95

depression

hypericum

placebo and

11 RCT

y/y/y/

Most of 8 placebo-controlled

Hypericum is superior to placebo

[28]

  

antidepressants

 

y/n

trials positive. 3 trials against

and seems equally effective as

      

standard medication with similar

standard medication

      

effects

 

Volz 2000

mild to

hypericum

fluoxetine

17+9

n/y/n/

No direct comparison of

Response rates are similar;

[29]

mod.

  

CCT

y/n

hypericum and fluoxetine

findings difficult to interpret

 

depression

    

available. Mean depression

because of the indirect comparison

      

score (HAMD) reduction in

 
      

hypericum trials 53%, in

 
      

fluoxetine trials 55%

 

Friede 98

anxiety in

hypericum

placebo,

8 RCT

?/y/y/

Trials collectively show reduction

Hypericum is effective for

[30]

depressed

 

amitriptyline

 

y/n

of anxiety symptoms over

depressed patients with anxiety

 

p.

    

placebo. Only 1 trial vs

 
      

amitriptyline

 

Garlic ( Allium sativum )

Lawrence

cardiovasc.

garlic

mainly placebo;

45 RCT

y/y/y/

37 trials consistently show small

Insufficient data to draw conclusion

2000 [31]

risk factors

 

no & other

 

y/y

short-term effects over placebo

regarding clinical cardiovascular

   

treatment

  

for cholesterol reduction. No

outcomes. Garlic preparations may

      

consistent effects on blood

have small, positive, short-term

      

pressure, promising effects re

effects on lipids

      

platelet aggregation and

 
      

fibrionolytic activity

 

Stevinson

hyperchol-

garlic

placebo

13 RCT

y/y/y/

Pooled total cholesterol

Available data suggest that garlic is

2000 [32]

esterolemia

   

y/y

reduction over placebo 0.41

superior to placebo. The size of the

      

(95% Cl -0.66 to -0.15) mmol/l;

effect is modest. The use of garlic

      

when analysis restricted to high

for hyperchol. is therefore of

      

quality trials 0.11 (-0.30 to 0.08)

questionable value

Silagy 94 &

cholesterol

garlic

placebo

16 RCT

y/p/y/

Pooled cholesterol reduction

Meta-analysis suggests positive

Neil 96

lowering

   

y/y

over placebo 0.65 (95% Cl 0.53–

effects but reviewers are sceptic

[33, 34]

     

0.76) mmol/l

(low quality; own replication

       

negative)

Warshafsky

cholesterol

garlic

placebo

5 RCT

p/y/y/

Pooled cholesterol reduction

Available evidence supports the

93 [35]

lowering

   

y/y

over placebo 0.59 (95%Cl 0.44–

use of garlic as one modality to

      

0.74) mmol/l

decrease cholesterol levels

Silagy 94

lowering

dried garlic

placebo, other

8 RCT

y/p/y/

Pooled reduction over placebo:

Garlic maybe of some clinical use

[36]

blood

(Kwai)

treatment

 

y/y

SBP 7.7 (95% Cl 4.3–11.0), DBP

in subjects with mild hypertension.

 

press.

    

5.0 (2.9–7.1) mm Hg

Further research needed

Kleijnen 91

cardiovasc.

garlic

placebo

18

p/p/y/

Most studies with shortcomings.

No clear conclusion drawn

[37]

risk factors

supplements

 

RCT/CCT

y/n

The majority of trials with pos.

 
      

results but inconsistent effect

 
      

sizes

 

Kleijnen 89

cardiovasc.

garlic &

unclear

10 RCT,

y/p/n/

All trials with severe

Inadequate evidence to justify

[38]

risk factors

onions

 

8 CCT

y/n

shortcomings. Fresh garlic with

supplementation, further research

      

beneficial effcts, onions and

needed

      

commercially available

 
      

supplements yielded

 
      

contradictory results

 

Jepson 97

lower limb

garlic

placebo

1 RCT

y/y/y/

Walking distance not

Insufficient evidence

[39]

atheroscler.

   

y/-

significantly different between

 
      

groups

 
  1. legend see table 1