Ivermectin has an approximate plasma half-life of 18 hours, and it, along with its metabolites, is primarily excreted in feces over an estimated period of 12 days.
Understanding How Long Ivermectin Stays in the Body
The duration ivermectin remains in the human body is determined by two main factors: its plasma half-life and its excretion time. These pharmacokinetic properties indicate how quickly the body processes and eliminates the drug.
Plasma Half-Life
The plasma half-life of a drug refers to the time it takes for the concentration of the drug in the blood plasma to reduce by half. For ivermectin, following oral administration, the plasma half-life in humans is approximately 18 hours. This means that after about 18 hours, half of the initial dose circulating in the bloodstream will have been processed or eliminated.
Excretion
While the half-life indicates the reduction in blood concentration, the complete elimination of ivermectin and its metabolites from the body takes longer. Ivermectin is primarily metabolized in the liver. The drug and its metabolites are then almost exclusively excreted in the feces.
Key details regarding excretion:
- Primary Excretion Route: Almost exclusively through feces.
- Estimated Excretion Duration: Over an estimated 12 days. This timeframe accounts for the complete removal of the drug and its breakdown products from the body.
- Minor Excretion Route: Less than 1% of the administered dose is excreted in the urine.
Summary of Ivermectin Pharmacokinetics
For a clearer understanding, here's a summary of ivermectin's key pharmacokinetic parameters:
| Parameter | Description |
|---|---|
| Plasma Half-Life | Approximately 18 hours following oral administration. |
| Metabolism | Occurs in the liver. |
| Primary Excretion | Almost exclusively via feces. |
| Excretion Duration | Estimated 12 days for complete removal. |
| Urinary Excretion | Less than 1% of the administered dose. |
In essence, while the blood levels of ivermectin significantly decrease within a day due to its half-life, the drug and its metabolites can be detected in the body, primarily in fecal matter, for up to an estimated 12 days.
