Published: April 2004
Publications
Diarrhoea with Beta-Blockers - Blast from the Past
Prescriber Update 25(1): 10
April 2004
Dr Natasha Rafter, Public Health Medicine Registrar, Auckland University
Diarrhoea is a possible, but not dose-related, side effect of beta-blocker therapy. If the diarrhoea is severe or persistent, withdrawal of the beta-blocker is recommended but this must be gradual to avoid harmful cardiovascular sequelae.
Reports of diarrhoea with carvedilol
Carvedilol is a non-cardioselective beta-blocker (blocks both β1 and β2 adrenergic receptors) with alpha (α1) blocking activity.1 It is indicated for the management of essential hypertension, angina pectoris and as adjunctive therapy in chronic heart failure.2
The Centre for Adverse Reactions Monitoring (CARM) has received four reports of diarrhoea with carvedilol (Dilatrend®). In three of the reports, severe diarrhoea developed within a week; and in the fourth case, the diarrhoea was moderate and began during the first month of carvedilol treatment. The doses of carvedilol ranged from 6.25mg to 25mg daily. All the individuals experienced improvement in their symptoms on stopping the medicine. In Australia, eleven cases have been reported to the Adverse Drug Reactions Unit.3
All beta-blockers can cause diarrhoea
Diarrhoea is a recognised adverse effect of the beta-blockers as a class,1 and there are cases documented in the literature.4 As with the other beta-blockers, the carvedilol data sheet describes gastrointestinal symptoms, such as diarrhoea, nausea and vomiting, as being a common occurence (with a frequency of between 1-10%) and not dose-related.2
Discontinue beta-blocker treatment gradually if diarrhoea persists
If the diarrhoea persists or is severe, treatment with beta-blockers may need to be withdrawn and alternative therapy commenced. However, if beta-blockers are stopped abruptly there is a risk of rebound hypertension, angina or myocardial infarction especially in individuals with ischaemic heart disease. Therefore, it is necessary to withdraw the beta-blocker gradually over two weeks while monitoring symptoms and blood pressure.1,2
Competing interests (author): none declared.
Correspondence to Dr Natasha Rafter, Auckland Regional Public Health Service, Private Bag 92605, Symonds St, Auckland. E-mail: nrafter@paradise.net.nz
References
- Cardiovascular drugs. In SC Sweetman (Ed) Martindale: The complete drug reference 33rd edn. 2002: Great Britain; Pharmaceutical Press, p.844-856.
- Roche Products (New Zealand) Limited. Dilatrend datasheet 07 February 2002. www.medsafe.govt.nz/Profs/Datasheet/d/Dilatrendtab.htm
- Personal communication, 11 November 2003. Executive Officer, Adverse Drug Reactions Unit, Therapeutic Goods Administration, Australia.
- Dutertre J-P, Machet L, Codjovi P, et al. Severe chronic diarrhoea secondary to celiprolol. Annals of Pharmacotherapy 1992;26(6):842-843.