Opioid painkillers compared

Compare all 32 opioid painkillers side by side, used for conditions such as colonic diseases, functional, diarrhea, dysentery, bacillary. Opioid painkillers are the Opioid Agonist class. They share one FDA-defined mechanism but differ in approved uses, prescription status, brand-vs-generic options, price, and FDA recall-safety record — which our independent rating scores. The highest-rated is loperamide hydrochloride.

15 of 32 drugs in this class carry a pharmaranks safety score, ranging 40–72 out of 100 — computed from FDA recall records, not from reviews.

Rated against independent sources·Last updated July 30, 2026·How we rate

Top-rated opioid agonist: 1. Loperamide Hydrochloride · 2. Methadone Hydrochloride · 3. Sublimaze Preservative Free

Opioid Agonist drugs compared side by side, with pharmaranks' FDA recall-safety rating
Drug	Generic	Form	Status	Used for	Safety ratingFDA recall-based	Pharmacy pays
Loperamide Hydrochloride	—	Capsule	Prescription	Colonic Diseases, Functional, Diarrhea	72/100	$0
Methadone Hydrochloride	—	Injectable	Prescription	Opioid-Related Disorders, Intractable Pain	72/100	$0
Sublimaze Preservative Free	Fentanyl Citrate	Injectable	Prescription	Pain	72/100	$9
Sufenta Preservative Free	Sufentanil Citrate	Injectable	Prescription	Pain	72/100	—
Conzip	Tramadol Hydrochloride	Capsule	Prescription	Pain	70/100	$1
Duramorph Pf	Morphine Sulfate	Injectable	Prescription	Dyspnea, Intractable Pain	70/100	$3
Imodium A-D	Loperamide Hydrochloride	Capsule	Over-the-counter	Colonic Diseases, Functional, Diarrhea	70/100	$0
Infumorph	Morphine Sulfate	Injectable	Prescription	Dyspnea, Intractable Pain	70/100	$3
Methadose	Methadone Hydrochloride	Concentrate	Prescription	Opioid-Related Disorders, Intractable Pain	70/100	$0
Ultiva	Remifentanil Hydrochloride	Injectable	Prescription	Pain	70/100	—
Dilaudid	Hydromorphone Hydrochloride	Injectable	Prescription	Cough, Postoperative Pain	66/100	$1
Dilaudid-Hp	Hydromorphone Hydrochloride	Injectable	Prescription	Cough, Postoperative Pain	66/100	$1

The safety rating column is unique to pharmaranks — an independent 0–100 score from FDA regulatory recall data. Higher is safer. Not medical advice.

Best opioid agonist by condition

for functional colonic diseases for diarrhea for bacillary dysentery for opioid-related disorders for intractable pain for pain

Full ranking · 32 drugs

Frequently asked questions

What is the Opioid Agonist drug class?

Opioid Agonist is an FDA Established Pharmacologic Class (EPC) — a group of drugs that share a mechanism of action. pharmaranks lists 32 Opioid Agonist products, each independently rated.

Are all Opioid Agonist drugs the same?

No. Opioid Agonist drugs share the same core mechanism — that is why they sit in one FDA class — but they differ in their approved uses, available forms, whether they are prescription or over-the-counter, brand-vs-generic options and price, and their FDA recall-safety record.

Is "opioid painkillers" the same as the Opioid Agonist class?

Yes — "opioid painkillers" is the everyday name for the Opioid Agonist drug class. This page compares the 32 opioid painkillers pharmaranks rates, with our independent FDA recall-safety score for each.

What conditions do Opioid Agonist drugs treat?

Per NIH RxClass drug-classification data, Opioid Agonist drugs are used for conditions including colonic diseases, functional, diarrhea, dysentery, bacillary, opioid-related disorders, intractable pain, pain.

Which Opioid Agonist drug is best-rated?

By our independent rating, loperamide hydrochloride currently ranks highest among Opioid Agonist drugs. Ratings are based on FDA regulatory (recall-safety) data — always consult a professional.

Sources: the Opioid Agonist class definition and its member drugs come from the U.S. NLM RxClass (Established Pharmacologic Class); how the class works is summarized from Mu Receptors - StatPearls - NCBI Bookshelf. Ratings are pharmaranks’ independent FDA recall-safety analysis.