Simeticone is not suitable for some people. To make sure it's safe for you or your child, tell a pharmacist or doctor if you (or your child):

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Rarely, hypersensitivity reactions such as rash, pruritis, facial oedema, tongue oedema and respiratory difficulty have been reported. Simeticone often comes combined with other ingredients. It's important to read the leaflet that comes with the medicine, or the information printed on the box or bottle, to make sure the medicine is suitable for you or your child.You or the person who's unwell may also have a rash that's swollen, raised, itchy, blistered or peeling.

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you're breathing very fast or struggling to breathe (you may become very wheezy or feel like you're choking or gasping for air)Most adults and children, including newborn babies, can take simeticone. Who may not be able to take simeticone Simeticone is a very safe medicine and is generally not known to cause any side effects. Serious allergic reaction