Effectiveness of Laxatives in the Elderly - NIHR Health Technology ...

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Results
4.0
3.5
3.0
2.5
2.0
1.5
1.0
0.5
0
–0.5
–1.0
Change in BMs per week
FIGURE 5 Effect size by quality score (trials in the elderly only)
The actual agents used are heterogeneous so
it is difficult to make generalisations from this
small set of trials.
Bulk laxatives
One trial (Chokhavatia et al, 1988) compared
two bulk laxatives and found that bowel movement
frequency was greater with psyllium
than with calcium polycarbophil, although
there was no significant difference in consistency.
Patients preferred the latter laxative as
flatulence was less common. One trial (Pers
& Pers, 1983), in which two bulk plus stimulant
combinations were compared, found that
Lunelax ® was more effective than Agiolax ® ,
although the difference was non-significant
and there was little examination of other
outcomes. No differences in side-effects
were reported but the study is small and
may lack power.
A bulk plus stimulant combination (Agiolax)
was found to be more effective in terms of
frequency than an osmotic laxative, lactulose,
in two trials (Kinnunen et al, 1993; Passmore
et al, 1993a; b). Both trials also showed Agiolax
to be associated with greater consistency, although
only one trial showed a significant difference.
Pooling of the frequency data from both these
trials indicates an increase in bowel movement
2 4 6
Quality score
frequency of the order of about two per week
with Agiolax treatment compared with lactulose
(Figure 6). No treatment differences in adverse
effects were found but, given the small sample
sizes, the studies may have lacked the power
to detect any such differences.
Osmotic laxatives
The osmotic laxative, magnesium hydroxide,
was found to be more effective than a combination
of osmotic laxative plus fibre (Laxamucil ® )
in terms of both frequency and consistency
of stools (Kinnunen & Salokannel, 1987). In
addition, a comparison of two osmotic laxatives,
lactulose and sorbitol (Lederle et al, 1990),
suggested that sorbitol may be equal in effectiveness
to lactulose and may therefore be a cheaper
alternative. One study found a small significant
increase in frequency with lactitol compared with
lactulose (Doffoel et al, 1990), although stool
consistency appeared to improve more with
lactulose treatment.
Stimulants
Marchesi (1982) compared three herbal
mixtures of cascara, vitamin B and boldo
in varying amounts and showed that the
addition of a herbal mixture and vitamin
B 12 to cascara and boldo increased bowel
movement frequency.