How long does nitazoxanide 500 mg tablet stay in human body?

Nitazoxanide is a medication commonly used to treat various parasitic and viral infections, including giardiasis, cryptosporidiosis, and viral gastroenteritis. Understanding how long nitazoxanide stays in your system can be important for ensuring its effectiveness and avoiding potential side effects.

Half-Life of Nitazoxanide

The half-life of a medication is the time it takes for half of the drug to be eliminated from the body. For nitazoxanide 500 mg, the half-life is relatively short, typically ranging from 1 to 4 hours in adults. This means that after a dose of nitazoxanide, levels of the drug in the body decrease by half within this time frame.

Duration of Action

Despite its short half-life, nitazoxanide’s active metabolite, tizoxanide, has a longer half-life of approximately 20 hours. This means that while the parent drug, nitazoxanide, is quickly eliminated from the body, tizoxanide remains active for a longer period. This extended duration of action allows for less frequent dosing, often once or twice daily, depending on the condition being treated.


Nitazoxanide 200 mg and its metabolites are primarily eliminated through the feces, with only a small amount excreted in the urine. The exact time it takes for nitazoxanide to be completely eliminated from the body can vary depending on factors such as age, liver function, and overall health.

Factors Affecting Elimination

Several factors can affect how long nitazoxanide stays in your system, including:

  1. Liver Function: Impaired liver function can slow down the metabolism and elimination of nitazoxanide, leading to a longer duration of action.
  2. Age: Older adults may metabolize and eliminate nitazoxanide more slowly than younger individuals, leading to a longer half-life.
  3. Kidney Function: Although nitazoxanide is primarily eliminated through the feces, any impairment in kidney function could potentially affect its elimination.
  4. Dosage and Duration of Use: Higher doses of nitazoxanide or longer durations of treatment can lead to the accumulation of tizoxanide in the body, prolonging its effects.

Experts recommend

Experts generally recommend a multifaceted approach to treating parasitic and viral infections. This approach often includes:

  1. Antiparasitic or Antiviral Medications: Specific medications are used to target the parasite or virus causing the infection. These medications may vary depending on the type of infection and its severity.
  2. Symptomatic Treatment: Some infections may cause symptoms such as fever, diarrhea, or nausea. Symptomatic treatment, such as hydration, rest, and over-the-counter medications, may be recommended to manage these symptoms.
  3. Preventive Measures: Preventing the spread of infection is crucial. This may include practicing good hygiene, avoiding contact with infected individuals or contaminated surfaces, and using insect repellent to prevent parasite transmission.
  4. Follow-up Care: In some cases, follow-up care may be necessary to ensure that the infection has been fully treated and to monitor for any potential complications.

It’s important to consult with a healthcare provider for a proper diagnosis and treatment plan tailored to your specific condition.

FAQs on Nizonide (Nitazoxanide)

What is Nizonide?

Nizonide is a brand name for the drug nitazoxanide. It is an antiparasitic and broad-spectrum antiviral medication used to treat various infections caused by parasites and certain viruses.

What conditions does Nizonide treat?

Nizonide is used to treat a variety of infections, including giardiasis (a type of intestinal infection), cryptosporidiosis (a diarrheal disease), and certain types of viral gastroenteritis. It may also be used off-label for other infections, as prescribed by a healthcare provider.

How does Nizonide work?

Nizonide works by interfering with the energy metabolism of parasites and certain viruses, leading to their death or inhibition of their replication. It is effective against a wide range of pathogens, making it a versatile treatment option for various infections.

Is Nizonide safe?

Nizonide is generally safe when used as prescribed by a healthcare provider. However, like any medication, it can cause side effects in some people. Common side effects may include stomach pain, nausea, diarrhea, and headache. Rare but serious side effects may include allergic reactions or liver problems. It is important to discuss any concerns with your healthcare provider.

How is Nizonide taken?

Nizonide is typically taken orally, with or without food, as directed by a healthcare provider. The dosage and duration of treatment will depend on the specific condition being treated. It is important to complete the full course of treatment, even if you start to feel better.

Can Nizonide be used in children?

Nizonide is approved for use in children for certain infections, such as giardiasis and cryptosporidiosis. The dosage will depend on the child’s age and weight. It is important to follow the healthcare provider’s instructions carefully when giving Nizonide to children.

Can Nizonide be used during pregnancy or breastfeeding?

It is important to consult a healthcare provider before using Nizonide during pregnancy or breastfeeding. While there is limited information available, Nizonide may be used if the potential benefits outweigh the risks. Your healthcare provider can provide guidance based on your individual situation.

Is Nizonide available over the counter?

Nizonide is a prescription medication and is not available over the counter. It should only be used under the supervision of a healthcare provider.

What should I do if I miss a dose of Nizonide?

If you miss a dose of Nizonide, take it as soon as you remember. However, if it is almost time for your next dose, skip the missed dose and continue with your regular dosing schedule. Do not take a double dose to make up for a missed one.

How should Nizonide be stored?

Nizonide should be stored at room temperature, away from moisture and heat. Keep the medication out of reach of children and pets. Do not use Nizonide past its expiration date.

Can Nizonide interact with other medications?

Nizonide may interact with certain medications, including antacids containing magnesium or aluminum, which may reduce its effectiveness. It is important to inform your healthcare provider about all medications, supplements, and herbal products you are taking before starting Nizonide treatment.


In conclusion, while the half-life of nitazoxanide is relatively short, its active metabolite, tizoxanide, has a longer duration of action. This allows for less frequent dosing. Factors such as liver and kidney function, age, and dosage can affect how long nitazoxanide stays in your system. It’s important to follow your healthcare provider’s instructions regarding the dosage and duration of treatment to ensure its effectiveness and minimize the risk of side effects.