ENTEREG vs VIVITROL

Independent side-by-side comparison.

Rated against independent regulatory sources·Last updated August 18, 2026·How we rate

Possible drug interaction. ENTEREG and VIVITROL are different prescription medicines. Combining or switching between them can cause interactions — talk to a pharmacist or prescriber before making changes. This page is not medical advice.

Attribute	ENTEREG	VIVITROL
Rating	72/100	70/100
Pharmacy pays	—	~$36.35 /30
Type	RX	RX
Active ingredient	ALVIMOPAN	NALTREXONE
Manufacturer	Cubist Pharms LLC	Alkermes Inc
Dosage forms	Capsule	Kit
Drug class	Opioid Antagonist	Opioid Antagonist
Boxed warning	None	None
Treats	—	Alcoholism, Opioid-Related Disorders, Drug Overdose

entereg vivitrol

Rating

72/100

70/100

Pharmacy pays

—

~$36.35 /30

Type

Active ingredient

ALVIMOPAN

NALTREXONE

Manufacturer

Cubist Pharms LLC

Alkermes Inc

Dosage forms

Capsule

Kit

Drug class

Opioid Antagonist

Boxed warning

None

Treats

—

Alcoholism, Opioid-Related Disorders, Drug Overdose

Frequently asked questions

Which is better-rated, Entereg or Vivitrol?

By our independent rating, Entereg scores higher — 3.6 vs 3.5 out of 5 for Vivitrol. Ratings are based on FDA regulatory (recall-safety) data.

What is the difference between Entereg and Vivitrol?

Entereg contains Alvimopan, while Vivitrol contains Naltrexone — they have different active ingredients.

Ratings are based on FDA regulatory (recall-safety) data. This comparison is for general reference only — not medical advice. Always consult a licensed professional before choosing or switching a medication.