Importance of hypersensitivity in adverse reactions to drugs in the elderly.

BACKGROUND: The use of drugs in the elderly is very extensive because of the frequent occurrence of chronic diseases. Adverse drug reactions (ADRs) commonly occur in geriatric patients receiving multiple therapeutic regimens. In the literature, little attention has been given to ADRs in the elderly, and particularly to allergic reactions. OBJECTIVE: The aim of the present study is to provide data on possible inappropriate prescriptions in the elderly in relation to allergic reactions and to identify a list of drugs which are likely inducers of allergic reactions. METHODS: We retrospectively evaluated ADRs in patients referring to Immunoallergy Unit of Hospital Policlinico in Bari on the basis of Beers criteria. Among adverse reactions, hypersensitivity reactions were extracted and a comparison between different age groups was assessed. RESULTS: Out of 823 patients with ADRs, in 30.6% hypersensitivity drug reactions (HDR) were diagnosed. Data about drug intake, comorbidities and clinical presentation were collected, aiming to identify possible risk factors. An evaluation of drugs most commonly involved was assessed. CONCLUSIONS: HDR are reported to represent 5-10% of all ADRs, while in our study population the prevalence was about 30%. This suggests the need to develop strategies to minimize the incidence of drug allergy in the elderly, as well to reduce the phenomenon of inappropriate prescriptions.

Rupatadine for the treatment of urticaria.

INTRODUCTION: Rupatadine fumarate is a second-generation antihistamine provided with a potent, long-lasting and balanced in vivo dual platelet-activating factor (PAF) and histamine antagonist activity and it uniquely combines both activities at a high level of potency. Rupatadine has a rapid onset of action and a long-lasting effect, so a once-daily dosing is permitted, moreover is well tolerated by young adults and the elders. Rupatadine does not present the side effects of first-generation H1-antihistamines, such as somnolence, fatigue, headache, impaired memory and learning, sedation, increased appetite, dry mouth, dry eyes, visual disturbances, constipation, urinary retention and erectile dysfunction. AREAS COVERED: This study evaluates the effectiveness and safety of rupatadine in chronic urticaria (CU) and acquired cold urticaria (ACU), through a systematic review of the literature. EXPERT OPINION: Patients affected by urticaria are often discouraged because frequently their disease does not recognize a cause and it is unresponsive to treatments. Patients can control their symptoms assuming second-generation H1-antihistamines, such as rupatadine. Several randomized, double-blind, placebo-controlled trials testify effectiveness and safety of rupatadine in CU and ACU. However, further clinical trials to evaluate the efficacy of rupatadine in different urticaria subtypes and to test the safety of doses higher than 20 mg are encouraged.

Hypersensitivity reaction to ranitidine: description of a case and review of the literature.

Ranitidine is an H2-receptor antagonist which is usually well tolerated. Hypersensitivity reactions to ranitidine, as well as other H2 antihistamines, have been rarely described. We report the case of a 47-year-old woman who developed an anaphylactic reaction to ranitidine used as intravenous premedication before anesthesia induction. The patient's history revealed that previous use of oral ranitidine for a peptic ulcer disease did not cause any adverse reaction. Intradermal test with ranitidine at a dilution of 1:100 gave an intense positive reaction. The protective role of H2-receptor antagonists as premedication is still unclear and should be carefully reconsidered on the basis of the available controversial evidence and the possible risk of hypersensitivity reactions.