In a placebo-controlled study, cetirizine given at the high daily dose of 60 mg for seven days did not cause statistically significant prolongation of QT interval. People with kidney problems. A lower dose of cetirizine is often needed for people with kidney problems and Benadryl capsules cannot be split to achieve this. Other cetirizine products may be suitable - ask your doctor.

This medication can affect the results of allergy skin tests. Tell any doctor who treats you that you are using Benadryl. In most people Benadryl Allergy Liquid Release Capsules do not cause drowsiness. However, there are rare exceptions and you should take care when you use this product for the first time. If Benadryl Allergy Liquid Release makes you feel drowsy, do not drive or operate machinery. Undesirable effects are described according to MedDRA System Organ Class and by estimated frequency based on the post-marketing experience.

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Do not give this medication to a child younger than 2 years old. Always ask a doctor before giving a cough or cold medicine to a child. Death can occur from the misuse of cough and cold medicines in very young children.

In a six-week, placebo-controlled study of 186 patients with allergic rhinitis and concomitant mild to moderate asthma, cetirizine 10 mg once daily improved rhinitis symptoms and did not alter pulmonary function. This study supports the safety of administering cetirizine to allergic patients with mild to moderate asthma.Although cetirizine is a non-sedating antihistamine, occasionally some people may find it makes them feel slightly sleepy. Make sure you know how this medicine affects you before doing potentially hazardous activities such as driving or operating machines. If you do find this medicine makes you sleepy you should avoid drinking alcohol or using other medicines that cause drowsiness with it, as this could make any sleepiness or reduced alertness worse.

Express Delivery (Please be aware when you select Courier Next Day for northern parts of Scotland, DPD may take 2 days to deliver) In most people Benadryl Allergy Relief does not cause drowsiness. However, there are rare exceptions and you should take care when you use this product for the first time. If this product makes you feel drowsy, do not drive or operate machinery. Benadryl Allergy Relief should not be taken whilst under the influence of alcohol.At therapeutic doses, no clinically significant interactions have been demonstrated with alcohol (for a blood alcohol level of 0.5 g/L). Nevertheless, precaution is recommended if alcohol is taken concomitantly.