It's true I do not have children, however a search on Google will give you an idea of the scope of physician's overprescribing antibiotics and have been for years.
http://www.google.com/search?hl=en&q...otics&aq=f&oq=
There are self-limiting conditions which resolve themselves on their own without medication, but when the timing occurs upon demanding an antibiotic, many people will assume that it was the medication that solved the problem, when in fact it did not. This can result in simply money wasted to treat things that will clear up on their own, or be best managed with 'symptom relief' medications; to the more severe consequences of contrubiting to antibiotic resistant strains of bugs.
The CDC (Centers for Disease Control) even has an entire web area dedicated to this problem.
http://www.cdc.gov/drugresistance/co...now-and-do.htm
In addidtion, flare ups of Sinusitis may well be caused not by bacteria, but a viral infection, or allergy of which antibiotics have no effect on. In a Britsh medical study, they found many physicians prescribed antibiotics when they really didn't think they were necessary based on several factors, including parental pressure, time pressures, inability to correctly diagnose a bacterial from viral infection, even fear of losing client to another competing clinic.
http://www.sciencedaily.com/releases...0111162856.htm
http://www.google.com/search?hl=en&s...usitis&spell=1
http://www.google.com/search?hl=en&q...en&btnG=Search
Allergies, Sinusitis, & Athsma can all play a part in cronic Sinusitis. If your dr. is recommending allergy testing, blood work, or referral to a specialist, you might want to consider it. If there is more than one problem then treating only one will not take care of the other. There are some indications that all of these may have other factors causing these symptoms in which more testing may be necessary.
You mentioned that the main problems started when he started pre-school. There is always a possibility your child is picking up a virus the other kids are passing around, or could be exposed to something he's allergic to there rather than at home.
Since you've been through so many dr. visits, and repeated rounds of antibiotics and yet the problem is still there, it may well be time to consider another course of action to prevent or minimize future sypmtoms. If necessary maybe a second opinon with a different dr. or specialist.
Just a thought.
Regardless I hope whatever is causing the problem goes away soon.
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