Your friend's son definitely needs to be seen by a physician. Typically one who has pneumonia would have increased pain in his/her chest. At first glance I would say the flu is a high probability, but further assessment from a physician in the ER is recommended. Also, did his physician prescribe Vicodin for his sore throat? This is typically not done for strep ...
THANK YOU, I'm printing this and giving it to his father right now. I'll follow up with how he's doing as soon as I know.
Sandra
This may or may not be a strep throat. A number of other bacteria can cause a very sore throat that, on examination, resembles strep throat. The fact that he still has the symptoms you describe below indicates that he is seriously ill. Some strep infections, if they get into the blood and spread to other parts of the body, can be life threatening. From your description, he probably does have pneumonia. When a strep infection of the throat continues to hurt so bad that he "can't speak after a short period due to pain" he may have developed a peritonsillar abscess of the throat. This is a bad complication. If so, this could spread to tissues adjacent to the throat.
I think this person is in great danger. He should be seen immediately in a large hospital emergency room, be hospitalized and seen on an emergency basis by an Infectious disease specialist. In all likelihood he will require treatment with intravenous antibiotics.
Please give us a follow-up to let us know how he does.