A skin infection and dry mouth during sleep are not always directly related, but both can sometimes occur together due to dehydration, diabetes, mouth breathing, allergy, fever, stress, poor sleep, or side effects of certain medicines. Fungal or bacterial skin infections may also become more common if blood sugar levels are not well controlled. Dry mouth at night can increase discomfort, bad breath, and disturbed sleep if it continues regularly. Keeping the skin clean and dry may help prevent worsening of the infection. Avoid scratching or using strong steroid creams without proper medical advice because some creams may worsen fungal infections. Drinking enough water throughout the day, reducing caffeine, and avoiding smoking or alcohol may help improve mouth dryness. Sleeping with the mouth open, nasal blockage, or snoring can also contribute to dryness during sleep. Please consult a doctor if the skin infection spreads, develops pus, becomes painful, or if dry mouth continues with excessive thirst, weight loss, or frequent urination, as tests for diabetes or other conditions may be needed.