Strongest Pain Pills

Morphine was the first opioid discovered. It was the most commonly used and researched opioid for nearly two centuries. Today, morphine is the baseline that other opioids are compared to.
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Two hundred years after its discovery, morphine remains one of the most popular opioid painkillers in use — but it’s far from the strongest. Synthetic opioids hundreds to thousands of times stronger than morphine are now turning up on America’s streets and contributing to a wave of overdoses and deaths.

Opioid abuse is not a new phenomenon, but it has become a worsening epidemic. Opioid-related overdose deaths have doubled since 2000, making drug overdose the leading cause of death for Americans under the age of 50.

Among the factors fueling this deadly epidemic is the exploding popularity of potent synthetic opioids such as fentanyl, which is 50 to 100 times stronger than morphine, and its chemical cousin carfentanil, an elephant tranquilizer that is 10,000 times more powerful than morphine.

Every day, 91 Americans die from an opioid overdose and more than 1,000 people are treated in emergency departments for not using prescription opioids as directed.

Source: Centers for Disease Control and Prevention

Most opioids work in roughly the same way. They attach to receptors in the brain that send signals to block pain, slow breathing and create a sense of euphoria. But what makes one drug more powerful or euphoric than another is its unique chemical structure — and how quickly and tightly it binds to those pain receptors.

As one of the faster prescription opioids, fentanyl zooms through the blood-brain barrier to the brain’s opioid receptors with remarkable efficiency and hugs those receptors more tightly than many other drugs. These characteristics make fentanyl particularly deadly among opioids.

Of the 60,000 drug overdose deaths recorded in 2016 in the United States, 20,000 involved fentanyl. The death rate increased more than fivefold since 2013, when fentanyl was implicated in 3,105 fatalities.

In medical literature, the analgesic strength, or potency, of most painkillers is measured as a comparison to morphine. For example, oxycodone is roughly 50 percent stronger than morphine. Therefore, researchers might say the drug is 1.5 times as strong as morphine. A single dose of Tylenol or aspirin is about 360 times weaker than a dose of morphine.

Opioids Weaker than Morphine

While morphine is the pharmacologic standard bearer in the lineup of prescription opioids, there are several milder prescription painkillers on the market. These range from codeine, a common ingredient in many cough syrups, to tapentadol, a relatively new drug that is being marketed to patients requiring long-term opioid treatment, such as those suffering from diabetic leg pain.


Like morphine and heroin, codeine comes directly from the opium poppy plant. The drug is an ingredient in many cough syrups and is also prescribed to treat mild to moderate pain and diarrhea. Codeine, which is seven to 14 times less potent than morphine, comes in a variety of dosages. The opioid is often combined with Tylenol to increase both drugs’ analgesic effects.

Meperidine (Demerol, Meperitab)

A synthetic opioid similar to morphine, Demerol has been used to treat pain since the early 1940s. It is sometimes used for post-surgical pain relief. While it is about seven to 10 times less potent than morphine, caution must be exercised because Demerol produces a toxic byproduct in the body that can cause tremors and seizures, particularly in patients with kidney problems. For this reason, meperidine should only be used by patients with normal renal function. Because of its relatively short half-life, meperidine doesn’t work well for acute or chronic pain.

Tramadol (Ultram, Ultram ER)

This synthetic opioid was a popular prescription painkiller for decades before it made its debut in the United States in the 1990s. Tramadol, which is about one-tenth as potent as morphine, works similarly to morphine, targeting the brain’s mu-opioid receptors to block pain signals. While it is considered to be less addictive than other opioids, the potential for addiction still exists.

Tapentadol (Nucynta)

Stronger than tramadol but two to three times less potent than morphine, tapentadol can be used to treat moderate to severe pain that is acute or chronic. A relatively new drug that was first approved for use in the United States in 2008, tapentadol is frequently prescribed for controlling pain related to diabetic neuropathy. It comes in both immediate-release and extended-release formulations. Studies have shown lower rates of abuse with tapentadol than with similar narcotics.

Opioids Equivalent to Morphine

Morphine and its chemically similar cousin hydrocodone might be equal in strength — but they haven’t always been treated as such. For years, Vicodin and other drugs containing a mixture of hydrocodone and acetaminophen had less stringent prescribing regulations than other opioids.

Originally a Schedule III drug, Vicodin was once deemed to have a moderate to low potential for dependence and a lower abuse potential than other narcotics. Unfortunately, those laxer standards helped propel the combination opioid to become the most prescribed drug in the United States, contributing to widespread abuse of the substance.

In 2014, the federal government tightened its controls on hydrocodone/acetaminophen, elevating the combination drug to Schedule II status. This category is for substances considered to have a high potential for harm and abuse.

Vicodin’s popularity hasn’t waned much though. In 2016, American pharmacies and long-term care facilities dispensed 90 million prescriptions for Vicodin, making it the fourth most prescribed medicine in the nation, according to a report by the IQVIA Institute for Human Data Science.

Hydrocodone (Vicodin, Lorcet, Norco)

Equal in strength to morphine, hydrocodone is one of the most popular opioid medications on the market. As such, it’s also the most commonly abused substance in the nation, with 24 million Americans reporting they use hydrocodone for nonmedical purposes. Some of the most popular formulations of the drug, including Norco, Vicodin and Lorcet, contain hydrocodone in combination with acetaminophen.

Morphine (MS Contin, Avinza, Kadian, Oramorph)

Two centuries after it was first discovered, morphine remains one of the most widely used painkillers in the world, with more than 230 tons of morphine prescribed legally each year. Morphine is approximately three times as strong as codeine and “remains the standard against which all new medications for postoperative pain relief are compared,” according to Dr. Jonathan Moss, a professor of anesthesia and critical care at the University of Chicago.

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Opioids Stronger than Morphine

The opioid death toll in this country is growing rapidly, and increased use of the drugs is not solely to blame. It’s also because people are taking increasingly strong opioids recreationally. Among them is the potent painkiller fentanyl. Stronger still is carfentanil, an elephant tranquilizer so powerful that sometimes Narcan cannot even counter its effects.

Oxycodone (OxyContin, Percocet, Percodan, Roxicodone)

Milligram for milligram, oxycodone is about 50 percent stronger than morphine. At one time, oxycodone was rarely used in settings outside of hospice or cancer treatment. That changed, however, in 1995, when Purdue Pharma released a new extended-release formulation of the drug called OxyContin.

While the drug manufacturer touted OxyContin as nonaddictive and safe, the opposite was true. Amid Purdue’s aggressive marketing campaign, OxyContin prescriptions soared. The drug made its way onto the streets and into the hands of abusers who snorted and injected it, methods that increase the potency of the time-release medication.

Methadone (Methadose, Dolophine)

Three times stronger than morphine, methadone is often prescribed to help people recover from addiction to heroin and other opioid pain medications. It lessens the painful symptoms of opioid withdrawal, and it is effective at reducing cravings. It also lacks the euphoric effects of other opioids. Methadone can be taken in the form of a pill, a liquid or a wafer. It is sometimes used for pain management in cancer patients and others with chronic pain.

Hydromorphone (Dilaudid)

Though it has a comparatively shorter duration of effect than morphine, Dilaudid is five to 10 times stronger. Hydromorphone is a popular second-line treatment for pain after morphine, but it has a high potential for abuse and dependence. An extended-release version of hydromorphone called Palladone was pulled from the market in 2005 amid safety concerns when several patients died after mixing the medication with alcohol.


Depending on who is using it and how it’s consumed, heroin is approximately two to five times stronger than morphine. Heroin is a naturally occurring substance that comes from the seed pod of certain types of poppy plants. When it’s snorted, smoked or injected, heroin users experience a euphoric rush lasting several hours. The rush is followed by a state of stupor or sleep that may also last multiple hours. Though heroin’s heyday was in the 1960s and 1970s, there’s been a resurgence in heroin use in recent years — particularly among young people — as prescription painkillers have become increasingly expensive and harder to obtain.

Oxymorphone (Opana)

This controversial opioid is 10 times stronger than morphine when taken intravenously and about three times more potent than morphine in pill form. In 2017, Opana manufacturer Endo Pharmaceuticals agreed to pull the extended-release formulation of drug, Opana ER, from the market at the request of the Food and Drug Administration because of its high abuse potential. Individuals found ways to crush and inject the medication despite its hard coating, and intravenous use of the medication was associated with in a 2015 outbreak of HIV in Indiana and a 2011 outbreak of hepatitis C in New York.

Buprenorphine (Subutex)

Buprenorphine is an opioid doctors prescribe to help treat opioid addition. It can be 25 to 100 times stronger than morphine depending on the formulation and other factors. It suppresses withdrawal symptoms and cravings, but unlike methadone, which is dispensed through clinics, buprenorphine can be prescribed and dispensed at a physician’s office.

Fentanyl (Sublimaze, Duragesic, Subsys)

This synthetic opioid that killed pop icon Prince is 100 times stronger than morphine. It moves quickly from the blood stream into the brain and binds tightly to pain receptors, making a fentanyl overdose extremely difficult to counteract. Rescue attempts may require multiple administrations of the reversal agent Narcan. A side effect known as “wooden chest syndrome,” which causes rigidity of the chest wall, can make doing CPR compressions on an overdose victim impossible.

Approximately 2 to 3 milligrams of fentanyl — which is roughly the same size as two to three grains of table salt — can cause respiratory depression, respiratory arrest and even death.

Source: Drug Enforcement Administration

Prescription fentanyl comes in many forms, including lozenges, lollipops and transdermal patches that are applied to the skin. The drug is also created illicitly and sold on the street. Fentanyl is commonly mixed with heroin, cocaine and other chemicals in counterfeit pills.


Though molecularly similar to fentanyl, this synthetic opioid is 100 times stronger than its chemical cousin and 10,000 times more potent than morphine.

Carfentanil was never intended for use in humans. It is so lethal, in fact, that it’s been classified as a chemical weapon in international arms control treaties. The only legitimate use of the drug is as a tranquilizer for elephants and other large animals. Nevertheless, the lethal substance has made its way from labs in China onto American streets.

“Carfentanil is 1000 times more powerful than morphine, and we’ve seen a lot of carfentanil on the streets.”
Steve Collins, Director of the Central Florida High Intensity Drug Trafficking Area

Carfentanil is just one of the substances — along with fentanyl, heroin and a synthetic opioid called U-47700 — that’s been turning up in a deadly new street drug called “Gray Death.” A minuscule grain of the combination drug, which resembles a chunk of concrete, can kill someone instantly. Gray death was associated with 50 overdoses in Georgia over a three-month span in the first half of 2017, and the DEA confirmed that U-47700 caused 46 deaths nationwide in 2015 and 2016.

While powerful opioids may carry a high risk of accidental overdose and death, weaker opioids are not necessarily safer than stronger ones. All opioids are addictive and carry significant risks and potential side effects. If you are prescribed an opioid pain reliever, take it only as directed. If you are unsure how to take your medication, contact your doctor or pharmacist.

Medical Disclaimer: aims to improve the quality of life for people struggling with a substance use or mental health disorder with fact-based content about the nature of behavioral health conditions, treatment options and their related outcomes. We publish material that is researched, cited, edited and reviewed by licensed medical professionals. The information we provide is not intended to be a substitute for professional medical advice, diagnosis or treatment. It should not be used in place of the advice of your physician or other qualified healthcare provider.

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