Chlorhexidine is an effective antiseptic which is widely used in dentistry. Over recent years, it has also been used in other healthcare products as well as in cosmetics. Anaphylaxis to chlorhexidine has been increasingly reported throughout the world, including two incidents in the UK where chlorhexidine-containing mouthwash had been used to wash tooth sockets following recent tooth extraction. Chlorhexidine is under-recognized as a cause of anaphylaxis and dentists should be aware of its potential for serious adverse effects. Dentists need to consider whether the washing out of a tooth socket with chlorhexidine solution should be avoided in the treatment of established dry socket. On current evidence the potential risks of using chlorhexidine as irrigation solution for treating an established dry socket appears to outweigh any known benefit. CPD/Clinical Relevance: Chlorhexidine has the potential to cause anaphylaxis in the dental surgery.