Why is the oral dose of vancomycin tapered down in the treatment of C. diff?

[Mark C]

VH1of3- That doesn't really answer my question at all.
I'm asking about recurrences of the disease, as treatment of the primary disease usually doesn't involve a taper.

[VH1of3]

USES: This medication is an antibiotic used to treat infections.

HOW TO USE: Take this medication by mouth as directed usually three to four times a day for 7 to 10 days. For best results, take each dose at evenly spaced intervals around the clock. This will ensure a constant level of medication in your blood. Take this medication for the full time prescribed. Do not stop taking this without your doctor's approval. Stopping therapy too soon may result in a reinfection.

SIDE EFFECTS: Indigestion or stomach ache may occur. If any of these effects continue or become bothersome, inform your doctor. Notify your doctor if you develop: dizziness, difficulty hearing, fever or chills. In the unlikely event you have a serious allergic reaction to this drug, seek immediate medical attention. Symptoms of a serious allergic reaction include: rash, itching, swelling, severe dizziness, breathing trouble. If you notice other effects not listed above, contact your doctor or pharmacist.

PRECAUTIONS: Tell your doctor your medical history, especially of: kidney disease, hearing problems, stomach/intestinal problems, allergies (especially drug allergies). Vancomycin should be used only when clearly needed during pregnancy. Discuss the risks and benefits with your doctor. This drug is excreted into breast milk. Because the effect on a nursing infant is unknown, consult your doctor before you breast feed.

DRUG INTERACTIONS: Tell your doctor of all prescription and nonprescription medications you use, including: aminoglycosides (e.g., gentamicin, neomycin), amphotericin B, other antibiotics, live vaccines. If you will be undergoing treatment requiring anesthesia, tell the doctor/dentist you have been using vancomycin. Do not start or stop any medicine without doctor or pharmacist approval.

[tinmuning]

Vancomycin is tapered or every-other-day dosing is done in cases of additional attacks (because C. difficile wasn't completely eradicated from the colon) and vancomycin is needed to be given again. However, to prevent relapse & to reestablish normal bowel flora, the dosage given before cannot be given in the succeeding attack, therefore it must be reduced or tapered.