How long does an Invega shot stay in your system? Decoding the timeline for long-acting antipsychotics

October 9, 2025 •

3 min read

Invega is an antipsychotic medication available in several long-acting injectable formulations, each designed to release the active ingredient over a different period. Understanding how long an Invega shot stays in your system is crucial because, unlike oral medications, it can take months or even years for the injectable forms to be fully eliminated from the body.

Quick Summary

The elimination timeline for an Invega shot varies by formulation, with the active ingredient slowly clearing from the body. Factors like dosage, injection site, and individual renal function influence how long it remains detectable. Clearance can take many months or longer, and plasma levels decline gradually after discontinuation.

Key Points

Prolonged Elimination: Invega injections, especially the long-acting versions, remain in the body for months or even years after the last shot.
Formulation is Key: The clearance timeline depends on the specific product: Sustenna (monthly) takes months to clear, while Trinza (3-month) and Hafyera (6-month) take significantly longer.
Half-Life Varies: The apparent half-life differs for each formulation, ranging from weeks for Sustenna to several months for Hafyera, influenced by the slow release from the injection site.
Renal Function Matters: Since paliperidone is cleared by the kidneys, reduced renal function can prolong the time it takes for the drug to leave the system.
Gradual Decline: Discontinuation results in a slow, gradual decrease in plasma concentration, meaning the effects do not cease immediately.
Irreversible Once Injected: The medication cannot be physically removed or reversed after administration; the body must eliminate it naturally over a long period.
No Immediate Withdrawal: Due to the slow decrease in drug levels, immediate withdrawal symptoms are less common compared to abruptly stopping oral antipsychotics.

Understanding Invega's Long-Acting Formulations

Invega is the brand name for paliperidone, an atypical antipsychotic used to treat schizophrenia and schizoaffective disorder. The medication is formulated as paliperidone palmitate for long-acting intramuscular injections, including Invega Sustenna (monthly), Invega Trinza (every 3 months), and Invega Hafyera (every 6 months). These versions differ in how long they last in the body due to the slow dissolution of paliperidone palmitate at the injection site.

The Pharmacokinetics of Paliperidone Injections

For long-acting Invega injections, the concept of "apparent half-life" is influenced by the slow absorption rate from the injection site, which limits the drug's elimination.

Invega Sustenna (Once-Monthly) Elimination

Invega Sustenna is administered monthly, with the median apparent half-life of paliperidone ranging from 25 to 49 days after a single injection. Drug release can last up to 126 days, and complete elimination may take several months after discontinuation.

Invega Trinza (Once Every 3 Months) Elimination

Given every three months after stabilization on Sustenna, Invega Trinza has a median apparent half-life ranging from 84 to 139 days. The drug is detectable for up to 18 months, with plasma levels potentially remaining above a clinically relevant threshold for 10 to 14 months after discontinuation.

Invega Hafyera (Once Every 6 Months) Elimination

Administered every six months after treatment with Sustenna or Trinza, Invega Hafyera has a median apparent half-life of 148 to 159 days. Drug release can be longer than 18 months, and therapeutic concentrations may be maintained for 14 to 20 months after discontinuation.

Comparison of Invega Formulations

To help illustrate the distinct elimination timelines, here is a comparison table:


Feature	Invega Sustenna (Monthly)	Invega Trinza (3-Month)	Invega Hafyera (6-Month)
Injection Frequency	Once every 4 weeks	Once every 3 months	Once every 6 months
Median Apparent Half-Life (Post-Single Dose)	25-49 days	84-139 days	148-159 days
Longest Release Duration (Post-Single Dose)	Up to 126 days	Up to 18 months	Longer than 18 months
Time to Complete Clearance	Several months (e.g., 4-8 months)	Can take longer than 18 months	Can take more than 2 years
Therapeutic Levels After Discontinuation	N/A	10-14 months (simulation)	14-20 months (simulation)

Factors That Influence How Long Invega Stays in Your System

Several factors can affect the individual timeline for how long Invega remains in a person's body:

Renal Function: Since paliperidone is primarily eliminated unchanged through the kidneys, patients with renal impairment will have slower clearance.
Body Mass: Body mass index (BMI) can influence clearance, though typically not enough to require dosage adjustments.
Injection Site: Deltoid injections may lead to slightly faster absorption compared to gluteal injections for some formulations.
Cumulative Dosing: Long-term therapy results in steady-state concentrations, and clearance begins only after the last dose, prolonging the elimination period.

What Happens After Discontinuation?

Discontinuing Invega leads to a slow, gradual decrease in plasma concentration due to its extended-release nature. The effects, and potential side effects, will not stop immediately. It is crucial to discuss discontinuation with a healthcare provider to manage the risk of symptom return.

Is it Possible to Remove or Reverse the Effects of an Invega Shot?

Once administered, an Invega injection cannot be physically removed or reversed. The body must naturally process and eliminate the drug over its prolonged timeline. Discussing treatment and potential discontinuation with a healthcare provider is essential.

Conclusion

How long an Invega shot stays in your system varies significantly based on the formulation, ranging from several months for Sustenna to over a year for Trinza and Hafyera. This is due to the drug's slow release from the injection site. Factors like renal function and injection site also play a role. The medication cannot be quickly removed or reversed once injected. Always consult with your doctor regarding Invega treatment and discontinuation.

Disclaimer: This article is for informational purposes only and does not constitute medical advice. Consult a qualified healthcare professional for personalized guidance regarding Invega.

Frequently Asked Questions

No, Invega does not stay in your system forever, but it can take a very long time to be completely eliminated. Depending on the formulation (Sustenna, Trinza, or Hafyera), the elimination process can take anywhere from several months to a couple of years after the last injection.

You cannot speed up the elimination of Invega from your system. The medication is designed to be released slowly from the muscle tissue over an extended period. Once injected, the body must process and eliminate it at its own rate.

After a single shot of Invega Sustenna, the medication releases for up to 126 days, and the apparent half-life is between 25 and 49 days. Total clearance can take several months, likely between 4 and 8 months.

Following a single shot of Invega Trinza, the medication can remain in the system for up to 18 months. The apparent half-life is much longer (84-139 days), and simulations show plasma concentrations can be sustained for 10-14 months after discontinuation.

With Invega Hafyera, the medication is released for over 18 months, and therapeutic concentrations can persist for 14-20 months after the last injection. The apparent half-life is around 148-159 days.

Missing an Invega injection can cause your symptoms to return. The necessary steps depend on the specific formulation and how long ago the last dose was received. It is important to contact your doctor immediately to decide on the appropriate course of action.

Since Invega contains paliperidone, which is structurally related to risperidone, there is a possibility it could affect some drug tests, depending on the test type. However, standard drug tests are typically not designed to detect antipsychotics, so it is unlikely to cause a false positive for common substances like opioids. If you have concerns, disclose your medication use to the testing facility.