Hello, Salvia can cause lip irritation. Use of vasoline can coat and protect your lips. If you are recovering from any respiratory infection, this can be transferred by your salvia. This is common with strep. If you have a viral reaction, you will need time for the virus to get out of your system. Your choice of products may help lessen symptoms until the virus is gone. Evaluate your sleeping habits. Any dental concerns such as grinding your teeth or mouth breathing? This can dry your lips and throat. Are there any other oral symptoms such as a coated tongue or red tissue that can indicate a fungal infection? This can require a prescription such as Nystatin. Probiotics or Acidophilus can help reduce chances of infection. Other medications can produce side effects and your medical history should be reviewed. Seasonal changes such as dealing with dry heat can cause tissue reaction, chapped lips and dehydration. Drink water and more water to be sure to be well hydrated. Avoud irritants and limit acidic intake. Consider visiting a dermatologist if symptoms persist. Consider a visit to your dentist if you are due for a checkup to look for additional oral factors. Thank you for your inquiry.