Erzofri Dosage

Generic name: Paliperidone palmitate 39mg in 0.25mL
Dosage form: injection, extended-release suspension
Drug class: Atypical antipsychotics

Medically reviewed by Drugs.com. Last updated on Mar 18, 2025.

Recommended Dosage

For patients who have never taken oral or injectable paliperidone, or oral or injectable risperidone, establish tolerability with oral paliperidone or oral risperidone prior to initiating treatment with ERZOFRI.

ERZOFRI must be administered by a healthcare professional as an intramuscular injection. Do not administer ERZOFRI by any other route. For detailed preparation and administration instructions, see Dosage and Administration (2.7).

See Table 1 for dosage recommendations for ERZOFRI in the treatment of schizophrenia in adults or the treatment of schizoaffective disorder in adults as monotherapy and as an adjunct to mood stabilizers or antidepressants.

The initial dosage of ERZOFRI is 351 mg on treatment Day 1 administered in the deltoid muscle. Following the initial dose, monthly doses can be administered in either the deltoid or gluteal muscle.

Table 1: Dosage Recommendations for ERZOFRI
Indication	Initial Dose (deltoid) Day 1	Monthly Dosage* (deltoid or gluteal)	Maximum Monthly Dosage
* Administered 4 weeks after the first injection. † The recommended monthly dosage for treatment of schizophrenia is 117 mg. Some patients may benefit from lower or higher monthly doses within the additional available strengths (39 mg, 78 mg, 156 mg, and 234 mg). ‡ Adjust dose based on tolerability and/or efficacy using available strengths. The 39 mg strength was not studied in the long-term schizoaffective disorder study.
Schizophrenia	351 mg	Monthly Dosage* (deltoid or gluteal)	Maximum Monthly Dosage	39 mg to 234 mg†	234 mg
Schizoaffective disorder	351 mg	78 mg to 234 mg‡	234 mg

Adjust dosage monthly depending on clinical response and tolerability. When making dose adjustments, the pharmacokinetic profile of ERZOFRI should be considered, as the full effect of the dose adjustment may not be apparent for several months.

Missed Doses

Dosing Window

To avoid a missed monthly dose, patients may be given the injection up to 7 days before or after the monthly time point.

Missed Dose

If a dose of ERZOFRI is missed, follow the dosing instructions provided in Table 2.

Table 2: Management of a Missed Dose of ERZOFRI
TIMING OF MISSED DOSE	DOSING
4 to 6 weeks since last injection	Resume regular monthly dosing as soon as possible at the patient's previously stabilized dose, followed by injections at monthly intervals.
More than 6 weeks to 6 months since last injection	Resume the same dose the patient was previously stabilized on (unless the patient was stabilized on a dose of 234 mg, then the first 2 injections should each be 156 mg) in the following manner: Administer a deltoid injection as soon as possible. Administer a second deltoid injection 1 week later at the same dose. Thereafter, resume administering the previously stabilized dose in the deltoid or gluteal muscle 1 month after the second injection.
More than 6 months since last injection	Restart dosing with recommended initiation (see Section 2.1, Table 1): Administer a 351 mg deltoid injection on Day 1. Thereafter, resume administering the previously stabilized dose in the deltoid or gluteal muscle 1 month after the initial injection.

Use with Risperidone or with Oral Paliperidone

Paliperidone is the major active metabolite of risperidone. Exercise caution if ERZOFRI is co-administered with risperidone or with oral paliperidone for extended periods of time. Safety data involving concomitant use of ERZOFRI with other antipsychotics is limited.

Dosage Recommendations for Patients with Renal Impairment

For patients with mild renal impairment (creatinine clearance ≥ 50 mL/min to < 80 mL/min [Cockcroft-Gault Formula]), initiate ERZOFRI with a dose of 234 mg on treatment Day 1 in the deltoid muscle. Follow with the recommended monthly dosage of 78 mg, administered in either the deltoid or gluteal muscle. Adjust monthly dosage based on tolerability and/or response within the strengths of 39 mg, 78 mg, 117 mg, or 156 mg. The maximum monthly dosage is 156 mg for patients with mild renal impairment.

ERZOFRI is not recommended in patients with moderate or severe renal impairment (creatinine clearance < 50 mL/min).

Dosage Modifications for Concomitant Use with Strong CYP3A4 Inducers and/or P-gp Inducers

Avoid using a strong inducer of CYP3A4 and/or P-gp during the one-month dosing interval for ERZOFRI, if possible. If administering a strong inducer is necessary, consider managing the patient using paliperidone extended-release tablets.

Switching from Other Antipsychotics

There are no systematically collected data to specifically address switching patients with schizophrenia or schizoaffective disorder from other antipsychotics to ERZOFRI or concerning concomitant administration with other antipsychotics.

Switching from Oral Antipsychotics

Previous oral antipsychotics can be gradually discontinued at the time of initiation of treatment with ERZOFRI. The recommended initial dosage of ERZOFRI is 351 mg on treatment Day 1, administered in the deltoid muscle. See Table 3 for subsequent monthly dosage recommendations for ERZOFRI in patients switching from oral extended-release paliperidone tablets.

Table 3: Dosage Recommendations Following Initial Dose of ERZOFRI in Patients Switching from Oral Extended-Release Paliperidone Tablets
	Paliperidone Extended-Release Tablet	ERZOFRI
Dosing Frequency	Once Daily	Once every 4 weeks
	12 mg	234 mg
Dose	9 mg	156 mg
	6 mg	117 mg
	3 mg	39 mg to 78 mg

Switching from Long-Acting Injectable Antipsychotics

When switching patients currently at steady-state on a long-acting injectable antipsychotic, initiate ERZOFRI therapy in place of the next scheduled injection.

Continue ERZOFRI at monthly intervals. The initial dosing regimen as described in Section 2.1 is not required. See Table 1 for recommended monthly dosing. Based on previous clinical response and tolerability, some patients may benefit from lower or higher doses within the available strengths (39 mg, 78 mg, 117 mg, 156 mg, and 234 mg).

If ERZOFRI is discontinued, its pharmacokinetic characteristics must be considered. As recommended with other antipsychotic medications, the need for continuing existing extrapyramidal symptoms (EPS) medication should be re-evaluated periodically.

Preparation and Administration Instructions

To be prepared and administered by a healthcare professional only.
Read the instructions for preparation and administration below for preparation and administration considerations.
For deltoid or gluteal intramuscular injection only. Do not inject by any other route.
Administer the initial dosage of ERZOFRI in the deltoid muscle. Subsequent monthly dosages may be administered in the deltoid or gluteal muscle.
As a universal precaution, always wear gloves.
Do not substitute any component of the drug kit.

The kit contains a prefilled syringe and 2 safety needles (a 1 ½-inch 22 gauge needle and a 1-inch 23 gauge needle).

ERZOFRI is for single use only.

Step 1. Select Needle

For Deltoid injection	For Gluteal injection

If the patient weighs less than 90 kg, use the 1-inch 23 gauge needle (needle with blue colored hub)	Use the 1 ½-inch 22 gauge needle (needle with gray colored hub) regardless of patient's weight
If the patient weighs 90 kg or more, use the 1 ½-inch 22 gauge needle (needle with gray colored hub)

Step 2. Prepare for Injection

a. Open needle pouch	b. Shake vigorously for at least 10 seconds	c. Remove cap

First, peel the safety needle pouch half way open. Place on a clean surface.	Shake the syringe vigorously for a minimum of 10 seconds to ensure a homogeneous suspension.	While holding the syringe upright, remove the rubber tip cap with an easy counterclockwise twisting motion. Do not touch syringe tip.
d. Attach needle	e. Remove needle sheath	f. Remove air bubbles

Grasp the needle sheath using the plastic peel pouch. Attach the safety needle to the luer connection of the syringe with an easy clockwise twisting motion. Do not remove the pouch until the syringe and needle are securely attached.	Pull the needle sheath away from the needle with a straight pull. Do not twist the sheath as the needle may be loosened from the syringe.	Bring the syringe with the attached needle in upright position to de-aerate. De-aerate the syringe by moving the plunger rod carefully forward.

Step 3. Inject

Inject the entire contents intramuscularly slowly, deep into the selected deltoid or gluteal muscle of the patient. Do not administer by any other route.

Step 4. After Injection

Secure Needle	Dispose properly
a	Dispose of the syringe and unused needle in an approved sharps container.

b

c

After the injection is complete, use either thumb or finger of one hand (a, b) or a flat surface (c) to activate the needle protection system. The needle protection system is fully activated when a 'click' is heard.