5 highly effective yet addictive opioid painkillers

Usually these painkillers are taken post surgery or due to an injury but are highly addictive

By Sadaf Naushad
|
February 02, 2026
5 highly effective yet addictive opioid painkillers

Opioids are quite potent drugs that relieve pain and produce feelings of euphoria, and should only be taken for short periods of time for acute pain, such as after an injury or surgery.

Regardless of their strength, all opioids are potentially addictive and can result in an overdose if misused.

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However, different opioids induce different effects and risks depending on their frequency of use and method of administration.

The following pain medication list includes commonly misused and abused opioids and opiates from strongest to weakest in potency.

Opioids and opiates are controlled substances with a high potential for abuse, dependence, and tolerance and should be administered under supervision.

1. Carfentanil:

Carfentanil is a synthetic drug 10,000 more powerful than morphine, and 100 times more potent than medical-grade fentanyl itself.

It is primarily used by veterinarians to sedate large animals such as elephants and is not indicated for human use, but occasionally it is found on the black market.

Even minuscule doses, however, can be fatal, and many deaths have occurred due to carfentanil being laced into heroin or other drugs unknown to the user.

2. Fentanyl:

Fentanyl is also a synthetic opioid that is up to 50 times more potent than heroin. Fentanyl is a prescription drug quite rarely prescribed for patients to manage severe pain after surgery, but due to fentanyl’s potency and potential for abuse, it is most often administered very slowly into the system via transdermal patch or lozenge.

Fentanyl on the black market, however, is not usually a product of prescription drug diversion. According to the Drug Enforcement Administration, most fentanyl on the street arrives from China or Mexico where it was manufactured in illicit labs and sold to cartels and dealers or to individuals through the Internet.

Like carfentanil, a very small dose (even incidental skin exposure) of Fentanyl can kill a person, about .25 of a milligrams. Fentanyl overdose deaths are on the rise, as most of the 5,500 opioid-related fatalities in 2014 involved Fentanyl.

3. Heroin:

Heroin, the is the third strongest narcotic and is a semi-synthetic opioid derived from morphine, a natural compound that comes from the opium poppy. Heroin is the only completely illegal, schedule I drug (drugs wi accepted medical use and a high potential for abuse) included in this list, as most opioids can be obtained through a prescription, whereas heroin is not considered to have an accepted medical use.

Heroin has a very strong potential for abuse, especially when injected. It can also be consumed, however, by snorting or smoking, and is often found as a whitish powder, or a black sticky substance (black tar heroin).

When injected, heroin enters the bloodstream and the brain much faster than other opioids, creating immediate intense feelings of euphoria.

4. Hydromorphone:

Hydromorphone is another potent opioid that is up to 8 times more potent than morphine. It is prescribed as a severe painkiller, under the brand name Dilaudid, and induces feelings of sedation and relaxation.

Hydromorphone is a schedule II drug (substances with a high potential for abuse, severe psychological or physical dependence risk, and recognized medical use).

It is commonly misused as a substitute for heroin because it can be dissolved in water and injected into the bloodstream to experience rapid and intense effects similar to heroin.

5. Oxymorphone:

Even though it’s at number 5, oxymorphone is still a very strong opioid. Oxymorphone may be prescribed to treat moderate to severe pain. It most often comes in tablet form but is sometimes prescribed as an injectable. It can be misused orally or by snorting or injecting.

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