Hye! As you said you are having herpes labialis frequently.. Your skin of affected lip is sensitive. Therefore you feel burning sensetion after eating salty items. Some time you feel salty taste in your mouth , that can be due to dehydration.. Less water intake or bacterial infection in salivary glands .. Poor oral hygine. To improve, you drink enough water, do betadine gargles, do regular dental cleaning. For herpes labialis, take tab. Acyclovir 400 mg thrice day for 2 weeks, then onward take the same tab in pulse.. Means, 400 mg twice a day for 5 days , 5 days gap , ............. , again for 5 days.. Likewise..for 2 to 3 years, So that relapse of herpes will be prevented. Tab. Levamisole 50 mg for long time will improve immunity. .. Ok