Dilaudid vs Morphine vs Fentanyl vs Oxycodone: The Opioid Strength Ladder

Street drugs in New Jersey can also contain animal sedatives such as xylazine and medetomidine, which naloxone does not reverse, so give it anyway.

Which is strongest: Dilaudid, morphine, fentanyl, or oxycodone?

Fentanyl, by a wide margin. Then Dilaudid (hydromorphone). Then oxycodone, the opioid in Percocet. Morphine is the reference point the others are scored against.

The ranking measures one thing: how few milligrams of each drug it takes to do what a set amount of morphine does. It does not tell you which is safer, which lasts longer, or how to swap one for another.

What “stronger” actually means

It means more potent, which is narrower than it sounds. All four are full opioid agonists, and the labels say that, as with all full agonists, there is no ceiling on pain relief; what limits the dose is side effects, including slowed breathing. Enough morphine does everything enough fentanyl does, including stopping a person’s breathing.

Potency only changes the amount. A drug that is five times as potent needs a fifth of the weight; one that is a hundred times as potent needs a hundredth. Fentanyl is not a different kind of drug from morphine. It is dangerous because the amount that matters is so small. NIDA notes that as little as 2 milligrams of fentanyl, the amount of a few grains of salt, can be fatal. At that scale nobody can measure by eye.

The more potent the opioid, the smaller the mistake it takes to overdose.

Dilaudid vs morphine

Is Dilaudid stronger than morphine?

Yes. Taken by mouth, hydromorphone counts for about five times morphine per milligram in the CDC’s table. The pain relief and the risks are the same kind.

Chemically they are close relatives: the label describes hydromorphone as a hydrogenated ketone of morphine. Their half-lives are similar, about two hours after an IV dose. What separates them in practice is the number on the bottle. The same milligram figure means a very different dose for each, and that is where mix-ups get dangerous. Both labels call for lower starting doses when the liver or kidneys are impaired, and any switch between them is the care team’s call, starting lower than any chart suggests.

What is stronger than morphine?

Per milligram, by the CDC’s 2022 table for oral doses unless noted:

• Hydromorphone (Dilaudid): about 5 times
• Methadone: listed at 4.7, though methadone behaves unlike the others and is managed differently, covered in our medication guide
• Oxymorphone: about 3 times
• Oxycodone: about 1.5 times
• Fentanyl: about 100 times by injection, per its label

Hydrocodone is listed as equal to morphine. Codeine, tramadol, and tapentadol are weaker. Outside the pharmacy, NIDA warns that some fentanyl-like drugs, such as carfentanil, are stronger still and more likely to cause an overdose.

Dilaudid vs fentanyl

Fentanyl is far stronger. Its injection label puts 100 micrograms at about the pain relief of 10 milligrams of morphine, roughly 100 to 1. The CDC puts hydromorphone by mouth at about 5 to 1. The routes differ, but the gap is plain. In New Jersey, though, the hospital comparison is the less useful one.

Prescription fentanyl is given by clinicians in measured micrograms, during surgery and anesthesia, or as skin patches for people with severe, lasting pain who are already tolerant to opioids. The fentanyl people actually encounter is illegally made. The state’s Commission of Investigation reported in December 2025 that more than 90 percent of drugs seized by New Jersey law enforcement over the prior two years tested positive for illicit fentanyl. A pill sold as Dilaudid, or as oxycodone, that did not come from a pharmacy may be fentanyl, and a convincing stamp and color prove nothing.

Dilaudid vs Percocet

Percocet is oxycodone plus acetaminophen, the drug in Tylenol. Per milligram, the hydromorphone in Dilaudid is roughly three times as potent as the oxycodone in Percocet, going by the CDC factors of 5 and 1.5. Percocet tablets contain 2.5 to 10 milligrams of oxycodone, each with 325 milligrams of acetaminophen.

That makes the comparison lopsided in a second way. The Percocet label warns that acetaminophen has caused acute liver failure, sometimes requiring transplant or ending in death, mostly at more than 4,000 milligrams a day and often when more than one acetaminophen product is involved. Dilaudid carries no acetaminophen. With Percocet, every extra tablet taken for the opioid adds 325 milligrams the liver has to handle.

Half-life and duration: how long each one lasts

What half-life means here

Half-life is how long the body takes to clear half of the drug from the blood. It is not how long the effect lasts. Fentanyl shows the gap clearly: its label gives a terminal half-life of about 3.7 hours, yet a single IV dose relieves pain for only 30 to 60 minutes. Fentanyl reaches the brain fast and then redistributes into muscle and fat, and the label notes it is released from those tissues slowly. A 2023 review in the Journal of Addiction Medicine suggests that in people who use illicit fentanyl heavily, that buildup may prolong exposure.

Dilaudid half-life

About 2.3 hours after an IV dose, and about 2.6 to 2.8 hours for the tablets and liquid, per the label. Oral doses peak in the blood in half an hour to an hour. The tablets are labeled for use every four to six hours as needed.

How long does IV Dilaudid last?

The label does not give a duration for an IV dose. What it gives is a hospital starting schedule: a dose every 2 to 3 hours, injected slowly over at least two to three minutes, which staff then adjust while watching the patient’s breathing. That is a schedule for a monitored bed, not a measure of how long the drug works. For comparison, a single morphine injection into muscle relieves pain for about 3 to 4 hours, and an IV fentanyl dose for 30 to 60 minutes.

Effects through a vein arrive fastest, and so does the breathing risk. The fentanyl label puts onset at almost immediate by IV, against 7 to 8 minutes by injection into muscle, and the peak effect on breathing at 5 to 15 minutes after an IV dose. The same label warns that the effect on breathing can last longer than the pain relief. A drug whose relief wears off in an hour or two also gets repeated often, which means more doses, more chances for a bad one, and withdrawal that returns quickly.

Why short-acting opioids bring withdrawal on fast

The shorter the half-life, the sooner the body notices the drug is gone. SAMHSA’s treatment guide for opioid use disorder (TIP 63) gives this general pattern:

That is a typical course, not a schedule. Early signs are runny nose, watery eyes, sweating, yawning, and restlessness; later come cramps, diarrhea, vomiting, goosebumps, and dilated pupils. MedlinePlus describes the symptoms as very uncomfortable and withdrawal as usually not life threatening. Usually is not always: MedlinePlus notes that vomiting and diarrhea can cause dehydration and mineral imbalances, and that vomit can be breathed into the lungs, and TIP 63 lists dehydration in the most severe stage. TIP 63 adds that after the first phase, many people have weeks or months of low mood, cravings, poor sleep, and heightened pain.

Fentanyl is the exception people ask about. Its buildup in fat and muscle complicates withdrawal and the timing of a first buprenorphine dose, and researchers say it needs more study. A 2024 review of withdrawal care in the fentanyl era found precipitated withdrawal was a real concern, but rates were low and it was reduced or managed with low-dose or high-dose buprenorphine starts. Our opioid detox guide covers how New Jersey programs handle it.

Why conversion charts are not for self-dosing

Online conversion tables look like arithmetic. They are not. The CDC gives the reasons: the ratios cannot account for individual differences in genetics and how the body handles each drug, and when clinicians switch someone from one opioid to another, they typically start well below the calculated amount, because tolerance to one opioid only partly carries over to the next. The CDC also says its factors should not be used for decisions about treating opioid use disorder.

The second trap is a tolerance lower than the person thinks. TIP 63 warns that people who finish withdrawal are at risk of overdose. After time away from opioids, in detox, jail, or a hospital stay, the old amount can stop a person’s breathing. Keep naloxone where people can reach it, and do not use alone. Where to get it in New Jersey, and how to use it, is in our naloxone guide for families.

Detox from Dilaudid, oxycodone, morphine, or fentanyl

The drug changes the timing. It does not change the plan. Medical detox for any of these draws on the same tools, including buprenorphine or methadone to control withdrawal and cravings, and other medications for sleep, nausea, and diarrhea. MedlinePlus says clonidine can ease anxiety, sweating, muscle aches, and cramping, but does not reduce cravings.

Timing matters most with buprenorphine. Started while a full opioid like hydromorphone or fentanyl is still on the receptor, it can trigger precipitated withdrawal, a sudden, severe version of the same illness. A good program asks what you took and when, and plans the first dose around the answer. Tell them if the pills did not come from a pharmacy.

Detox ends withdrawal. It does not treat the addiction, and stopping there is risky. People who stayed on methadone or buprenorphine died of overdose at several times lower rates than people who had left it, according to a 2017 BMJ meta-analysis of cohort studies. Our medication guide compares the options.

In New Jersey

Fully insured New Jersey plans and the State Health Benefits and School Employees’ plans cannot require prior authorization for the first 180 days per plan year of in-network treatment your own physician, psychologist or psychiatrist finds medically necessary. Self-funded employer plans, Medicare and Medicaid are not covered by that rule. NJ FamilyCare (Medicaid) members and people without insurance can call the IME Addictions Access Center at 1-844-276-2777, which screens callers and refers them to treatment. ReachNJ, at 1-844-732-2465, is the state’s treatment referral line. Both answer 24/7. Same-day admission is sometimes possible; it is not guaranteed. For what a specific plan covers, see the insurance guides.

Under the state’s Naloxone365 program, anyone 14 or older can get naloxone anonymously at participating pharmacies; StopOverdoses.nj.gov lists them.

Periscope Behavioral Health, which publishes this site, is opening a medical detox in Hammonton, Atlantic County, expected Summer 2027. Until then, the admissions line of our publisher, Periscope Behavioral Health, at (888) 313-3583, can talk through options in New Jersey and Florida, including facilities Periscope operates. What a plan covers depends on the plan and the facility’s network status.

What the ladder is good for

Understanding, mostly. It explains why a hospital measures fentanyl in micrograms and morphine in milligrams, and why a pill that is secretly fentanyl leaves so little room for error. It will not tell you a safe amount of anything. What actually lowers the risk is plainer: pills only from a pharmacy, naloxone within reach, and a clinician planning any switch or stop.