Angiotensin II antagonists - an assessment of their acute toxicity

In Germany, increasing prescription rates of angiotensin II antagonists resulted in rising enquiries to Poisons Information Centres (PICs) during the last decade. Therefore, we aimed to assess their acute toxicity for deriving triage recommendations.

An observational case series with data collected retrospectively from eight PICs in Austria, Germany and Switzerland. Inclusion criteria were monoexposure, defined dose, and documented follow-up.

In total, 206 cases of exposures to angiotensin II antagonists were included (candesartan, 94; eprosartan, 3; irbesartan, 20; losartan, 26; olmesartan, 16; telmisartan, 18; and valsartan, 29). The median dose expressed as a multiple of their maximum daily dose for adults adjusted to body weight (MDDw) was 2.3 in children and 6.8 in adults. Patients involved were 150 children with a median age of 2 years and a median body weight of 13 kg and 56 adults with a median age of 47 years and a median body weight of 70 kg. Most children remained asymptomatic (82.7%), 16.7% developed minor symptoms. Only once, a low blood pressure of 60/40 mm Hg required intravenous fluids after ingestion of a 8.75-fold MDDw of candesartan by a 2.5-year-old toddler. Among adults, 53.6% remained asymptomatic while almost half of the patients suffered from minor (37.5%) or moderate (8.9%) symptoms.

As no or only minor symptoms were observed after ingestion of less than a fivefold MDDw in both children and adults, only symptomatic patients and those who have ingested a fivefold MDDw or higher dose should be referred for medical assessment.