C19. Nitrofurantoin. Phosphomycine. Pharmacotherapy of urinary tract infections.

Question 1

What is the MOA of Phosphomycin?

Answer 1

Phosphomycin is used as prodrug trometamol. It inhibits formation of N-acetyl muramic acid.

Question 2

What is the MOA of Nitrofurantoin?

Answer 2

Nitrofurantoin concentrates in urine and is reduced inside bacteria by flavoproteins → highly reactive intermediates → cause damage to ribosomes, DNA and metabolic processes.

Question 3

What spectrum does phosphomycin cover?

Answer 3

Gram + (Staph) and Gram - (E. coli, Klebs, Enterobacter, Proteus).

Question 4

What are some kinetic parameters to keep in mind with phosphomycin?

Answer 4

It is only therapeutic in urine, and safe in pregnancy!

Question 5

What spectrum does nitrofurantoin cover?

Answer 5

Good activity against Staph, Strep, Enterococcus and E. coli.

Question 6

What are the side effects of nitrofurantoin?

Answer 6

1. GI symptoms: Nausea, Flatulence (more rarely).
2. CNS symptoms: Headache
3. Pulmonary hypersensitivity reactions and skin reactions (itching, urticaria, hair loss)

Question 7

What are the indications of nitrofurantoin?

Answer 7

1. UTI- Urinary tract infections

Question 8

What are Urinary Antiseptics?

Answer 8

Urinary antiseptics are oral drugs that are rapidly excreted into the urine and act there to suppress bacteriuria. The drugs lack systemic antibacterial effects but may be toxic. Urinary antiseptics are often administered with acidifying agents because low pH is an independent inhibitor of bacterial growth inurine. The most widely used of these compounds is nitrofurantoin which is of value in the management of urinary tract infections.