What is the appropriate action to take for a patient presenting with blisters on the lips and tongue?

For a patient presenting with blisters on the lips and tongue, it is critical to assess the severity of the condition, particularly if the presentation suggests airway compromise due to swelling or lesions that may obstruct breathing. The presence of blisters in the oral cavity can indicate serious underlying issues, such as an allergic reaction or a viral infection, both of which may cause significant swelling.

Preparing to intubate is the appropriate action if there are concerns about the patency of the airway. This step is essential because airway management may become necessary if the blisters lead to swelling that compromises breathing. Prompt intubation can prevent respiratory failure and ensure that the patient maintains adequate oxygenation during treatment.

The other options may not address the immediate life-threatening concerns presented by the condition. While antihistamines could help in cases involving allergic reactions, they might not be sufficient if there is significant airway edema. Oral hydration is a supportive measure but doesn't address airway management if swelling is present. Similarly, applying a topical ointment might provide localized relief but would not be appropriate in a situation involving potential airway compromise. Thus, preparing for intubation ensures that any potential airway obstruction is proactively managed, protecting the patient's ability to breathe.