What should be done if a client shows signs of an allergic reaction during a service?

If a client shows signs of an allergic reaction during a service, the most appropriate action is to stop the service and consult medical assistance. This response is crucial because allergic reactions can range from mild to severe and may escalate rapidly. Immediate cessation of the treatment helps prevent further exposure to the allergen and mitigates the risk of exacerbating the client's condition.

Taking prompt action by stopping the service allows for a thorough assessment of the client's reaction and enables the professional to provide any necessary first aid or comfort while waiting for medical help. This can include monitoring the client and ensuring their safety until further assistance is available.

Continuing the service could endanger the client by delaying necessary intervention, while merely applying a cold compress without professional medical consultation may not adequately address the seriousness of the situation. Offering a discount is incorrect as it doesn't address the client's health and safety and may come off as insensitivity to their reaction. Thus, prioritizing the health and well-being of the client through immediate cessation of services and seeking medical assistance is the most responsible course of action.