Recovery Begins Here
Call 24/7 (855) 960-5456

We’re open everyday 24/7
Get help now
Free & confidential

(855) 960-5456

Strongest to Weakest Opioids: Dosages and More

The opioid crisis has emerged as the biggest public health crisis in America in a generation. As hundreds of thousands of people struggle with the abuse of prescription and illegal opioids, there is confusion about the differences between all the different kinds of opioids.

While all opioids interact with the brain and body in the same way, not all opioids are created equally. Some opioids are helpful, some are illegal, some are dangerous, but all are risky in nature! This list of the strongest to weakest opioids, along with their dosages and more, will answer questions of why some opioids are prescribed the way they are.

Read on to learn more about the different types of opioids and the dangers associated with them.

History and Mechanism of Opioids

To understand the strength and uses of even the most potent of opioids, it is important to look at what opioids actually are. Opioids are derived from chemical compounds found in the poppy plant. The practice of using the seeds in the poppy plant to relieve pain, or even to experience a pleasurable buzz, has been in practice for thousands of years.

The molecules in the chemical compounds naturally bind to the opioid receptors in the brain, the spinal cord, and other parts of the body; the result of doing this is that they reduce the intensity of pain signals sent from the body to the spinal cord and the brain. 

Synthetic formulations of the chemicals in the poppy seeds can lead to very powerful forms of opiates, which can effectively completely nullify the pain signals and put the user in a state of powerful euphoria and sedation, like being in a very deep and pleasurable sleep.

This has very obvious practical applications. For a generation, opioids were the go-to drug for doctors and pharmacists to treat chronic and persistent pain. Patients who had severe work- or age-related injuries, recovering from sports injuries, recovering from surgery, or experiencing cancer pain would be given opioids to help them cope with the physical discomfort. 

Dependence and Illegal Use

Opioids can do a lot of therapeutic good, but they are incredibly powerful. Many people have found the painkilling and euphoric effects very difficult to resist, to the point of taking more opioids even when there is no necessity to do so. The changes to the brain can be habit-forming, and the longer a person uses opioids, the more this becomes a source of psychological dependence; eventually, it becomes almost impossible to experience pleasure in any other way. Trying to stop taking opioids causes very distressing physical and psychological symptoms, which can compel a person to increase their rate of consumption, thereby deepening the dependence on opioids.

illicit substances

Not all opioids have legitimate medical uses. Heroin, one of the most widely trafficked and lethal of illicit substances, is also derived from the chemical compounds in the opium plant. While heroin does induce the same analgesic and euphoric effects as prescription opioids, it is so lethally potent that it has no accepted or legal use in the United States.

However, many people who develop a psychological dependence on prescription opioids turn to heroin because of the chemical similarities between the two, and because heroin is ultimately cheaper and more plentiful than prescription opioids.

Even then, new formulations of opioids – some for medical purposes, some by black market drug lords trying to come up with the next big product to sell – have increased the threshold of what constitutes the strongest opioid.

Fentanyl: The Strongest Opioid

An example of this is fentanyl, a drug that has made headlines for being 100 times more potent than morphine and 50 times as potent as heroin. Fentanyl is the most powerful opioid that has a medical application. It is used for the treatment of moderate-to-severe amounts of chronic pain when other forms of relief have failed.

Like many other opioids, fentanyl depresses the respiratory system, often taking effect within mere minutes and putting patients into a state of deep sedation. Even in this context, it is still dangerous. Medical News Today explains that there is enough of the opioid in oral formulations of the medication to induce a fatal overdose in a child. Fentanyl is so potent that it is administered in doses of only micrograms, as even 2 mg (milligrams) (the size of four grains of salt) will kill an average adult.

Fentanyl has many illegal derivatives and analogs (drugs that are unlawfully designed to be almost identical to the original). However, these analogs are much stronger than the fentanyl itself because they are often mixed with other substances. This is done so that the black marketeers making these drugs can keep their own costs down, but it exponentially increases the risk to the users. They have no idea what they are injecting into their bodies. Accidental overdoses, to the point of death, are tragically common.

An example of a fentanyl analog is carfentanil, which is more than 100 times more potent than fentanyl itself. By some estimates, it is 5,000 times stronger than heroin. It is so strong that its only accepted use is as a tranquilizer for elephants; there is no medical use for humans.

It only takes 0.02 mg of carfentanil, “an amount akin to a speck of dust,” in the words of Fox News, to induce a deadly overdose in humans. Police and public health officials fear that the effective invisibility of carfentanil will lead to accidental exposure.

Even people who inject heroin intravenously are in danger of consuming carfentanil if their heroin has been cut with this particular fentanyl analog. As an opioid, carfentanil is so deadly that some governments fear it could be used in a terrorist attack as a weapon of mass destruction.

Begin the path to
lasting recovery.

Call Now (855) 960-5456

Heroin Overdose

Fentanyl and carfentanil have made headlines over the last couple of years, but heroin is still the most infamous opioid, known by some as “one of the most potent and addictive substances that exists.”

 Thirty milligrams of heroin is enough to kill an adult, and no amount of the drug is legal to own or use. As a Schedule I controlled substance, it has no accepted or established medical application.

The opioid epidemic did not start with heroin, but heroin dominates the conversation today. Even as fatality rates from prescription opioids began to level out, heroin deaths increased across the country in 2010.

The U.S. Centers for Disease Control and Prevention notes that of the people who use heroin, as many as 75 percent turned to heroin because of a previous dependence on prescription opioids.

Many people

OxyContin and the Opioid Epidemic

Heroin has been trafficked in the United States since the early 20th century, but the opioid crisis itself was the result of pharmaceutical companies aggressively pushing prescription opioids directly to consumers in the 1990s. The wave of unnecessary prescriptions for the generic opioid oxycodone, sold as OxyContin, has been blamed for kickstarting the addiction epidemic in America. The Daily Beast writes that a simple change to the formulation of OxyContin – ostensibly to make OxyContin less addictive – made it too expensive for addicted users to keep using it, so they turned to heroin instead.

But without medications like oxycodone and hydrocodone (Vicodin), it’s unlikely that heroin would have been catapulted into the forefront. Oxycodone was first designed for the treatment of moderate to severe pain. The marketing blitz by its manufacturer, Purdue Pharma, was a “commercial triumph” for the pharmaceutical industry, according to the American Journal of Public Health; OxyContin became one of the most popular drugs in America, and billions of dollars were made in sales and advertising.

However, oxycodone always had its own risks for creating physical problems and psychological dependence in users. While not as immediately strong as heroin or fentanyl, its nature as an opioid can still lead to respiratory depression and a reduced heart rate. If users continue to load their systems with the medication, this can lead to brain damage and respiratory arrest and failure, ultimately culminating in an overdose. The dosage at which this happens depends largely on the patient’s individual tolerance levels as well as the degree to which the oxycodone has already been abused. The Pain Medication journal calculated that the most typical dosage of oxycodone dispensed within a two-month period to a patient who succumbed to an oxycodone overdose was a low as 10 mg for the immediate-release formulation of the medication.

Codeine: Low Danger But Still Risky

codeine dangers

Not every opioid is as deadly as heroin or oxycodone, but they all carry some risk of becoming habit-forming if taken for long enough. An example of this is codeine, one of the weaker opioids in the family. It is used for the treatment of mild-to-moderate pain, and it has been traditionally included in many cough medicines because of its effectiveness in suppressing the cough reflex that comes with having a cold. In some countries, getting codeine does not even require a doctor’s prescription; however, other countries like Australia have changed their policies because of a significant increase in the recreational and off-label abuse of codeine.

In America, the U.S. Drug Enforcement Administration has classified that painkillers that contain only codeine, or that have more than 90 mg of codeine per dosage unit, be listed in its Schedule II list of controlled substances. This is the second-most restrictive status for controlled substances, but it acknowledges that there are still legitimate medical applications for the codeine.

However, when codeine is not the primary chemical compound in a medication (as in the case of Tylenol), the regulations go only as high as Schedule III due to the “moderate-to-low physical dependence.” The DEA warns that even for Schedule III substances, the risk of psychological dependence is still high. Some states allow over-the-counter codeine sales if the content of the codeine in the medication is low enough.

Nonetheless, abuse of codeine does happen, and it can still physical and psychological problems similar to those of other, more powerful opioids. Everyday Health recommends that patients not take more than 360 mg of codeine a day for their pain. Patients who miss taking a regularly scheduled dose of their codeine should not take two doses to make up for the mistake; they should instead continue with their normal routine.

Opioid medications can help patients who really need relief for their pain, but the same properties that can be a blessing can also make the medications very dangerous. Knowing how opioids work, and how different opioids rank in their levels of strength, is vital information for making the right health care decisions.


(August 2018). How Did Opium Poppies Get Their Painkilling Properties? Live Science. from

(March 2018). What Are Opioids And Why Are They Dangerous? Mayo Clinic. from

(June 2017). 51 Percent Of Opioid Prescriptions Go To People With Depression And Other Mood Disorders. STAT News. from

What Are Opioids? American Society of Anesthesiologists. from

(October 2017). Everything You Need to Know About Fentanyl. Medical News Today. from

Fentanyl Transdermal (Rx). Medscape. from

(May 2017). Police Show How Much Fentanyl It Takes To Kill You. from

(July 2018). Fentanyl Analogs Nearly Double Their Overdose Death Toll. MDEdge. from

(April 2018). Run-ins With Carfentanil: The Opioid 5,000 Times More Potent Than Heroin. Fox News. from

(September 2016). Why Fentanyl is Deadlier Than Heroin, in a Single Photo. STAT News. from

(January 2017). Heroin Overdose Data. Centers for Disease Control and Prevention. from from

(April 2018). How OxyContin Kicked Off The Heroin Epidemic. The Daily Beast. from

(October 2014). Why is Oxycodone (OxyContin)? Everyday Health. from

(February 2009). The Promotion and Marketing of OxyContin: Commercial Triumph, Public Health Tragedy. American Journal of Public Health. from

(July 2014). Prescription Histories And Dose Strengths Associated With Overdose Deaths. Pain Medication from

(July 2015). The Availability Of Over The Counter Codeine Medicines Across The European Union. Public Health. from

(January 2017). Australia Bans Non-prescription Codeine To Fight Opioid Crisis. New Scientist. from

(May 2015). What is Codeine? Everyday Health. from

Have Questions? Call 24/7.
Calling Is Free & Confidential.

(855) 960-5456

COVID-19 Advisory: We are accepting patients and offering telehealth options. Click here for more information.