Medical Emergencies
Allergies

Some patients may have an allergic reaction to many of the materials and medications used in dental practice. The reaction may be a simple mild contact allergy, or could be a systemic reaction that results in breathing difficulties and circulatory problems (for details of diagnosis and management, see anaphylaxis ).

A patient may know they have an allergy to some materials and medications, but an allergic reaction can occur at any age even if there is no previous history.

The medical history must identify any known allergies and previous reactions, whether related to dental treatment or not.

Common allergies related to dentistry

Chlorhexidine
Chlorhexidine is an effective antiseptic which is widely used in dentistry and elsewhere. Anaphylaxis to chlorhexidine has been increasingly reported throughout the world, including two deaths in the UK where chlorhexidine-containing mouthwash had been used to wash tooth sockets following recent tooth extraction. Dentists should be aware of its potential for serious adverse effects. On current evidence the potential risks of using chlorhexidine as irrigation solution for treating an established dry socket appears to outweigh any known benefit. (Dent Update. 2016 Apr;43(3):272-4.)

Latex
This is a common allergen, and should be routinely avoided where possible. Use latex free gloves and dam, and use local anaesthetic cartridges that do not have latex bungs.

Mercury
Genuine allergy to mercury is extremely rare, but a number of patients may develop a lichenoid reaction on the oral mucosa.

Other metal allergies
Some patients are allergic to metals that are used in dental restorations, particularly Nickel, which is common in metal-based crowns, bridges, and dentures.

Antibiotics
Allergy to certain antibiotics is common. It is wise to restrict the prescription of antibiotics as much as possible, both to prevent sensitising an individual, and to prevent the emergence of resistant strains of bacteria.

Local anaesthetics
As well as the therapeutic agent, people can develop allergy to other constituents in a local anaesthetic, such as the preservatives and stabilisers.

Some patients may inform the dentist of a number of allergies to various foods and antibiotics, or they may have allergy related diseases such as eczema, asthma, allergic rhinitis, allergic conjunctivitis. It is wise to be prepared for the extra likelihood of an allergic reaction (or even anaphylaxis) to dental materials and medications with these individuals.