Recently, I have gotten sticky/gummy hair on only one part of my head. I have never colored my hair. I do get it permed, I haven’t had it done in months and months. This began a couple of weeks after I returned from a month long trip to Florida, California, Aruba, Cost Rica, and Mexico. I tired Nizoral shampoo as directed and it cleared it up the first time that I used it. I am in the second week of the 8 weeks it recommends (every 3-4 days), but it has come back. I would like to understand what is happening, why it is happening, and what I can do to cure this highly humiliating problem. Thank you so very much for your help.