Metronidazole is a prodrug, meaning it is administered in an inactive form. Its selective toxicity relies on the unique biochemistry of anaerobic and microaerophilic organisms. These parasites possess electron-transport proteins (like ferredoxin and flavodoxin) with a very low redox potential. Inside the parasite cell, metronidazole acts as an electron acceptor. These reduced electron-transport proteins donate electrons to the nitro group (-NO2) of metronidazole, reducing it to its active form, a short-lived nitroso free radical and other toxic intermediates. In oxygenated human cells, this reduction does not occur efficiently. The activated metronidazole metabolites then cause lethal damage to the parasite's DNA. They form unstable adducts with DNA bases, leading to DNA strand breakage, degradation, and inhibition of nucleic acid synthesis. This ultimately results in cell death. This mode of action makes it highly effective against organisms with anaerobic metabolism but generally safe for human cells, which utilize aerobic respiration.

Break down complex topics into smaller, manageable chunks for easier recall.

Zambia

• loveness Phiri – 1084 pts

• Visual Pathway Lesions
• Positive and Negative Symptoms
• Hallucinations and Delusions
• Antipsychotic Medications
• Emergency: Environmental Emergencies