If this has been brought on suddenly then this could be viral illness also known as acute viral pharyngitis.
Viral illnesses are often self-limiting and subside after running their due course for about 5 to 7 days.
The treatment is symptomatic. You will need to keep yourself hydrated. Start Tylenol 2 tablets every 6 hours, start on a decongestant and antihistamine, a combination, Claritin D twice a day is best.
Steam inhalations four times a day and lozenges to soothe the throat. I will also suggest saline water gargles four times a day.
This should start getting better within 48 to 72 hours, however, if this seems to be increasing in intensity then a visit to the Urgent Care or your PCP will be warranted for an examination and a more thorough evaluation.
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