Urinary Antiseptics Flashcards
Properties of Urinary Antiseptics
- these drugs exert antibacterial activity in urine with no systemic activity
- bacteriostatic, but when given with acidic agent (Ascorbic acid - Vitamin C) (urine pH < 5) they will become bactericidal
Spectrum of Urinary Antiseptics
Broad:
→ gram +ve
→ gram -ve
→ Proteus spp.
- only by Fosfomycin
What are Proteus spp.
Gram -ve bacteria that causes UTIs and alkalize urine; rendering any antiseptic ineffective
A.D.M.E of Urinary Antiseptics
A: well-absorbed in the GIT
M: rapid metabolism in the liver
E: excreted in urine, but the excretion rate is much higher than the metabolism rate; allowing some unchanged fraction of these drugs to reach the urine
Drug-Drug Interations of Urinary Antiseptics
Never given with Sulfonamides; because sulfonamides are insoluble and cause Crystalluria in acidic pH, and these drugs work at acidic pH (5 - 5.5)
Adverse Effects of Urinary Antiseptics
- GI distress
- NVD and anorexia
- Headache & Dizziness
- Vaginitis
- urinary antiseptics can disturb the balance of vaginal normal flora and cause opportunistic vaginitis
RoA of Nitrofurantoin
Oral
RoA of M. Mandelate & M. Hippurate
Oral
RoA of Fosfomycin
- Oral powder
- IV
MoA of Nitrofurantoin
UNKNOW MoA, but theorized as a DNA synthesis inhibitor
MoA of M. Mandelate & M. Hippurate
When the pH is <5, they will release their Formaldehyde group, which is bactericidal
MoA of Fosfomycin
Fosfomycin is a cell wall synthesis inhibitor that inhibiting the enolpyruvyl transferase called (MurA)
Indications of Nitrofurantoin
Uncontrolled chronic UTIs
Indications of Fosfomycin
Reserved as a last resort for severe UTIs; due to its unique MoA