Could my 5-week-old be allergic to something if he has a rashes?

My 5-week-old has developed a rash on his face and neck and appears to have dry, flaky skin on his ears. His face looks very red - almost like he has acne. Could he be allergic to something?

The changes you describe could be many things. Newborn acne is a possibility, even though it wasn't present until now. This usually looks like typical acne, with red bumps and "whiteheads", and is limited to the face and occasionally the neck or upper chest. This form of acne goes away on its own within a few months as your hormones clear from your baby's circulation. It could also be one of the many forms of dermatitis, including atopic dermatitis (eczema) and seborrhoeic dermatitis, which can affect the face, neck and ears. These usually appear as dry, scaly red patches and improve with hydrocortisone ointments and moisturisers. While babies have very sensitive skin that irritates easily, true allergies are extremely unlikely as a cause of the rash you describe. Your baby's GP or paediatric dermatologist can tell you more after examining your son.