pretty much always within 24 hours.

Usually the fever should lyse within 48 hours. If the fever is still present after 48 hours, tell your doctor about it including the temperature your son has.

Yeah. Antibiotics usually work within 24-48 hours. If its been just about 5 days, you should definitly give the doctor a call. But keep your son on the antibiotics until the doctor says so, because your not supposed to take taking them until they run their course.
I stopped taking antibiotics for a uti when I felt better and it came back.

After you start taking an antibiotic, how many days before your fever should go away?One week ———-Antibiotics are among the most frequently prescribed medications in modern medicine. Antibiotics cure disease by killing or injuring bacteria. The first antibiotic was penicillin, discovered accidentally from a mold culture. Today, over 100 different antibiotics are available to doctors to cure minor discomforts as well as life-threatening infections.

Although antibiotics are useful in a wide variety of infections, it is important to realize that antibiotics only treat bacterial infections. Antibiotics are useless against viral infections (for example, the common cold) and fungal infections (such as ringworm). Your doctor can best determine if an antibiotic is right for your condition.Although there are well over 100 antibiotics, the majority come from only a few types of drugs. These are the main classes of antibiotics.
Penicillins such as penicillin and amoxicillin
Cephalosporins such as cephalexin (Keflex)
Macrolides such as erythromycin (E-Mycin), clarithromycin (Biaxin), and azithromycin (Zithromax)
Fluoroquinolones such as ciprofloxacin (Cipro), levofloxacin (Levaquin), and ofloxacin (Floxin)
Sulfonamides such as co-trimoxazole (Bactrim) and trimethoprim (Proloprim)
Tetracyclines such as tetracycline (Sumycin, Panmycin) and doxycycline (Vibramycin)

Aminoglycosides such as gentamicin (Garamycin) and tobramycin (Tobrex)
Most antibiotics have 2 names, the trade or brand name, created by the drug company that manufactures the drug, and a generic name, based on the antibiotic’s chemical structure or chemical class. Trade names such as Keflex and Zithromax are capitalized. Generics such as cephalexin and azithromycin are not capitalized.

Each antibiotic is effective only for certain types of infections, and your doctor is best able to compare your needs with the available medicines. Also, a person may have allergies that eliminate a class of antibiotic from consideration, such as a penicillin allergy preventing your doctor from prescribing amoxicillin.

In most cases of antibiotic use, a doctor must choose an antibiotic based on the most likely cause of the infection. For example, if you have an earache, the doctor knows what kinds of bacteria cause most ear infections. He or she will choose the antibiotic that best combats those kinds of bacteria. In another example, a few bacteria cause about 90% of pneumonias in previously healthy people. If you are diagnosed with pneumonia, the doctor will choose an antibiotic that will kill these bacteria.

Other factors may be considered when choosing an antibiotic. Medication cost, dosing schedule, and common side effects are often taken into account. Patterns of infection in your community may be considered also.

In some cases, laboratories may help a doctor make an antibiotic choice. Special techniques such as Gram stains may help narrow down which species of bacteria is causing your infection. Certain bacterial species will take a stain, and others will not. Cultures may also be obtained. In this technique, a bacterial sample from your infection is allowed to grow in a laboratory. The way bacteria grow or what they look like when they grow can help to identify the bacterial species. Cultures may also be tested to determine antibiotic sensitivities. A sensitivity list is the roster of antibiotics that kill a particular bacterial type. This list can be used to double check that you are taking the right antibiotic.

2 days or 48 hours so i would call the docter soon it is obvious it ist working