Untitled Quiz

A class of drugs targeting anaerobic microorganisms.

A prototypical nitroimidazole, effective against anaerobic protozoa and bacteria.

Nitro group reduction by anaerobic proteins, creating reactive radicals that damage DNA.

Microbes that thrive without oxygen.

Limited clinical resistance to nitroimidazoles in E. histolytica, but some resistance can emerge in T. vaginalis.

While possible, it's not a significant concern widely yet.

Nitroimidazoles, like metronidazole, are used to treat diseases caused by Trichomonas.

Anti-protozoal and anti-anaerobic bacterial agents.

Metronidazole is a prodrug that is reduced by microbial ferredoxins into an active metabolite that damages the microorganism's DNA, leading to its death.

Metronidazole acts against a wide range of anaerobic bacteria, protozoa, and some anaerobic bacilos and cocci. Examples include Trichomonas vaginalis, Entamoeba histolytica, Giardia lamblia, and various anaerobic bacteria (e.g., Bacteroides).

Metronidazole can be given orally, intravenously, topically, and intravaginally, reaching therapeutic concentrations in various bodily fluids, including vaginal secretions, semen, saliva, breast milk, and cerebrospinal fluid (CSF).

Metronidazole is well absorbed orally, reaching a maximum concentration in 0.25-4 hours, with a plasma half-life of about 8 hours. It is extensively distributed, metabolized in the liver, and mostly excreted through urine.

Microbial resistance to metronidazole develops in some species, often due to changes in metabolic processes (like the decrease of PFOR enzymes), or changes that enhance the ability of bacteria to modify the drug before it can reach its active form.

In some bacterial species, such as Bacteroides, genes like nimA, nimB, nimC, nimD, and nimF encode for enzymes that inactivate the drug.

Common side effects of metronidazole include frequent and unpleasant but generally not severe effects.

Metronidazole is almost completely absorbed in the small intestine, with only 2% via vaginal administration and lower concentrations via topical administration.

250 to 500 mg orally every 8 hours

Nausea, vomiting, abdominal cramps, metallic taste, headache

Not used in individuals with neurological conditions.

Teratogenic in animals and should be avoided in pregnant women.

Can cause Disulfiram-like reaction (nausea, vomiting, headache) with alcohol.

Metronidazole can increase Warfarin's effect, requiring monitoring

Prolonged use can cause neurotoxicity, including dizziness, seizures, and confusion.

Used to treat bacterial infections, especially anaerobic ones.

Effective against anaerobic bacteria and some protozoa, often used in combination with other antibiotics.

Treatment of choice in specific infections like gingivitis, pericoronaritis, and some intra-abdominal infections, along with anaerobic bacterial infections after surgery.

Typically 200-400 mg every 8 hours for 5-7 days depending on the infection.

Often combined with penicillin, cephalosporins, or macrolides as it doesn't target aerobic bacteria.

Component of triple therapy for eradicating H. pylori in patients with peptic ulcers, often alongside clindamycin and an acid pump inhibitor.

First-line treatment for giardiasis and trichomoniasis.

Treatment for various forms of amebiasis, including acute dysentery, chronic intestinal amebiasis, and hepatic amebic abscesses.

Treatment for antibiotic-associated pseudomembranous colitis. Often combined with other antibiotics such as clindamycin or amoxicillin.

A class of antibiotics that target bacterial DNA replication by inhibiting the enzyme DNA gyrase.

A bacterial enzyme crucial for controlling DNA supercoiling during replication and transcription.

Older quinolones, like nalidixic acid, sometimes less effective.

Quinolones inhibit DNA gyrase, therefore altering the DNA structure crucial for replication. This DNA damage, and later the synthesis of protein needed to destroy the damaged DNA, leads to the death of bacteria.

Quinolones are bactericidal and need the help of exonucleases for complete bacterial destruction and death.

Quinolones are categorized based on their generations (First, Second, Third, Fourth).

An enzyme that affects the topology of DNA by controlling supercoiling and unwinding.

Causing the death of bacteria.

2 grams orally per day for 3 days or 600mg every 12 hours for 7 days (with meals). Children: 50 mg/kg/day for 3 days (with meals).

Secnidazole is a nitroimidazole with a faster, complete oral absorption and a longer half-life of 17-29 hours, compared to metronidazole's 8 hours. A single-dose of secnidazole (as 1 gram every 12 hours) can equal the curative effect of repeated doses of metronidazole or tinidazole.

Tinidazole is a nitroimidazole similar to metronidazole; however, it has a longer duration of action (approx. 12 hours). It is often seen as better tolerated.

Avoid alcohol consumption during metronidazole treatment, as it can cause a disulfiram-like reaction.

Administration should be taken with food to minimize nausea.

The antibacterial activity of quinolones was first observed in the purification process of chloroquine.

600mg every 12 hours for 5 days for oral infections. 2g once daily for 3 days in more serious oral infections.

Secnidazole is rapidly and fully absorbed orally.