Hello dear,welcome to healthcare magic forum. Your tonsil need antibiotic treatment only if there is infection at present.Penicillin vk taken for tooth problem will take care of tonsil infection as well.Also note that avoiding cold drinks and doing frequent warm saline gargles will help to reduce recurrent tonsillitis attacks.Keep good oral hygiene always. Regarding sun exposure,if you do not have history of photosensitivity reaction to penicillin,a little exposure wont harm much.But,overexposure to hot atmosphere may exacerbate your tooth/tonsil problem by causing repeated infections. I hope you will find this information useful.Thank you.