Diabetic diarrhea and lidamidine

What about clonidine for diarrhoea? A systematic review and meta-analysis of its effect in humans

BACKGROUND

Clonidine is considered an alternative treatment for refractory diarrhoea. The evidence in the literature is scarce and not conclusive. The present paper's purpose is to gather available evidence and provide a systematic answer regarding the effectiveness of clonidine for diarrhoea.

METHOD

We performed a systematic review of clonidine and its effect on diarrhoea. Meta-analysis was performed with a random effects model of the standardized mean difference (SMD) or the weighted mean difference and heterogeneity was quantified with I (2) and publication bias was assessed with Egger's and Begg's test. Subgroup analyses and meta-regression were performed to investigate sources of heterogeneity. Any empirical study describing use of clonidine for diarrhoea in humans independent of age was included. For the meta-analysis, papers had to provide sufficient data to produce an effect measure, while case reports were not included in the meta-analysis and are discussed narratively only.

RESULTS

A total of 24 trials and seven case reports were identified. Clonidine (median dose 300 μg/day) has been used for treatment of diarrhoea in irritable bowel syndrome, faecal incontinence, diabetes, withdrawal-associated diarrhoea, intestinal failure, neuroendocrine tumours and cholera; studies were also performed on healthy volunteers. Results indicate a strong effect of clonidine on diarrhoea (SMD = -1.02, 95% confidence interval [CI] -1.46 to -0.58) with a decrease of stool volume by 0.97 l/day, stool frequency by 0.4 times/day and increase in transit time by 31 minutes. In a sensitivity analysis of studies with functional diarrhoea and sample size over 10 subjects, the effect was similar -0.99 (95% CI -1.54 to -0.43). There is however significant heterogeneity and publication bias. Heterogeneity decreased in subgroup analyses by condition but not with other factors examined. A limitation of the present study includes small study effects.

CONCLUSION

Clonidine is effective for treatment of diarrhoea and should be considered as an alternative when all other medications have failed.

Adrenergic mechanisms in the control of gastrointestinal motility: from basic science to clinical applications

Over the years, a vast literature has accumulated on the adrenergic mechanisms controlling gut motility, blood flow, and mucosal transport. The present review is intended as a survey of key information on the relevance of adrenergic mechanisms modulating gut motility and will provide an outline of our knowledge on the distribution and functional role of adrenoceptor subtypes mediating motor responses. alpha1-Adrenoceptors are located postsynaptically on smooth muscle cells and, to a lesser extent, on intrinsic neurons; alpha2-adrenoceptors may be present both pre- and postsynaptically, with presynaptic auto- and hetero-receptors playing an important role in the modulation of neurotransmitter release; beta-adrenoceptors are found mainly on smooth muscle cells. From a clinical standpoint, adrenoceptor agonists/antagonists have been investigated as potential motility inhibiting (antidiarrheal/antispasmodic) or prokinetic agents, although at present their field of application is limited to select patient groups.

A double-blind crossover comparison of lidamidine, loperamide and placebo for the control of chronic diarrhoea

Fourteen patients with chronic diarrhoea, but no evidence of active organic disease, completed a double-blind crossover comparison of the anti-diarrhoeal effects of loperamide, placebo and the clonidine analogue, lidamidine. Failure of diarrhoea control led to early withdrawals from seven placebo- and six lidamidine-treatment periods, but there was only one early withdrawal during treatment with loperamide. Loperamide was found to be superior to lidamidine or placebo for the control of stool consistency in patients with chronic diarrhoea.

Antidiarrheal therapy. Prospects for new agents

Successful treatment of severe diarrhea has traditionally relied upon opiates or opiate derivatives. Recent advances in our understanding of intestinal fluid and electrolyte absorption have provided the opportunity to develop therapeutic agents specific for various points in the secretory and absorptive process. Present and proposed antidiarrheal agents, in addition to antimotility activity, will be capable of stimulating intestinal fluid absorption, inhibiting intestinal fluid secretion, or both. The mechanism(s) of action and clinical implications for proposed antidiarrheal agents are reviewed.