Opiate comparison
Encyclopedia
Opioid
s are a class of compounds that elicit analgesic
(pain killing) effects in humans and animals by binding to the μ-opioid receptor
within the central nervous system
. The following table lists commonly used opioid drugs and their relative potencies
. Values for the potencies of opioids listed on this table are given as taken orally unless another route of administration
is provided. As such, their bioavailabilities
differ, and they may be more potent when taken intravenously.
1 In simple terms, analgesic "strength" in this table means how much more or less potent the indicated drug is compared to morphine. The values can be used to calculate approximately equivalent dosages of different opioids.
Because some of these compounds (for example, codeine and tramadol, but not morphine) are prodrugs, differences amongst people in their liver enzymes (such as the cytochrome P450 enzyme CYP2D6
) may result in a significantly altered drug effect.
2 Because of their extreme potency, etorphine, carfentanil, and other similarly powerful opiates are only used for the sedation of large animals. Sufentanil is the strongest opioid used in human medicine.
Opioid
An opioid is a psychoactive chemical that works by binding to opioid receptors, which are found principally in the central and peripheral nervous system and the gastrointestinal tract...
s are a class of compounds that elicit analgesic
Analgesic
An analgesic is any member of the group of drugs used to relieve pain . The word analgesic derives from Greek an- and algos ....
(pain killing) effects in humans and animals by binding to the μ-opioid receptor
Mu Opioid receptor
The μ-opioid receptors are a class of opioid receptors with high affinity for enkephalins and beta-endorphin but low affinity for dynorphins. They are also referred to as μ opioid peptide receptors. The prototypical μ receptor agonist is the opium alkaloid morphine; μ refers to morphine...
within the central nervous system
Central nervous system
The central nervous system is the part of the nervous system that integrates the information that it receives from, and coordinates the activity of, all parts of the bodies of bilaterian animals—that is, all multicellular animals except sponges and radially symmetric animals such as jellyfish...
. The following table lists commonly used opioid drugs and their relative potencies
Potency (pharmacology)
In the field of pharmacology, potency is a measure of drug activity expressed in terms of the amount required to produce an effect of given intensity. A highly potent drug evokes a larger response at low concentrations, while a drug of lower potency evokes a small response at low concentrations...
. Values for the potencies of opioids listed on this table are given as taken orally unless another route of administration
Route of administration
A route of administration in pharmacology and toxicology is the path by which a drug, fluid, poison, or other substance is taken into the body.-Classification:Routes of administration are usually classified by application location...
is provided. As such, their bioavailabilities
Bioavailability
In pharmacology, bioavailability is a subcategory of absorption and is used to describe the fraction of an administered dose of unchanged drug that reaches the systemic circulation, one of the principal pharmacokinetic properties of drugs. By definition, when a medication is administered...
differ, and they may be more potent when taken intravenously.
| Analgesic/opioid | Strength1 (morphine) | Equivalent dose (10 mg morphine) |
|---|---|---|
| Aspirin Aspirin Aspirin , also known as acetylsalicylic acid , is a salicylate drug, often used as an analgesic to relieve minor aches and pains, as an antipyretic to reduce fever, and as an anti-inflammatory medication. It was discovered by Arthur Eichengrun, a chemist with the German company Bayer... (non-opioid) |
1/360 | nil |
| Diflunisal Diflunisal Diflunisal is a non-steroidal anti-inflammatory drug . It was developed by Merck Sharp & Dohme in 1971 after showing promise in a research project studying more potent chemical analogs of aspirin. It was first sold under the brand name Dolobid, marketed by Merck & Co., but generic versions are now... (NSAID, non-opioid) |
1/160 | 1600 mg |
| Dextropropoxyphene Dextropropoxyphene Dextropropoxyphene, manufactured by Eli Lilly and Company, is an analgesic in the opioid category. It is intended to treat mild pain and has, in addition, anti-tussive and local anesthetic effects. It has been taken off the market in Europe and the US due to concerns of fatal overdoses and... |
1/40 | 400 mg |
| Codeine Codeine Codeine or 3-methylmorphine is an opiate used for its analgesic, antitussive, and antidiarrheal properties... |
1/10 | 100 mg |
| Tramadol Tramadol Tramadol hydrochloride is a centrally acting synthetic opioid analgesic used in treating moderate pain. The drug has a wide range of applications, including treatment for restless legs syndrome and fibromyalgia... |
1/10 | 100 mg |
| Anileridine Anileridine Anileridine is a synthetic analgesic drug and is a member of the piperidine class of analgesic agents developed by Merck & Co. in the 1950s... |
1/4 | 40 mg |
| Pethidine Pethidine Pethidine or meperidine Pethidine (INN) or meperidine (USAN) Pethidine (INN) or meperidine (USAN) (commonly referred to as Demerol but also referred to as: isonipecaine; lidol; pethanol; piridosal; Algil; Alodan; Centralgin; Dispadol; Dolantin; Mialgin (in Indonesia); Petidin Dolargan (in Poland);... |
0.36 | 28 mg |
| Hydrocodone Hydrocodone Hydrocodone or dihydrocodeinone is a semi-synthetic opioid derived from either of two naturally occurring opiates: codeine and thebaine. It is an orally active narcotic analgesic and antitussive... |
0.6 | 17 mg |
| Morphine Morphine Morphine is a potent opiate analgesic medication and is considered to be the prototypical opioid. It was first isolated in 1804 by Friedrich Sertürner, first distributed by same in 1817, and first commercially sold by Merck in 1827, which at the time was a single small chemists' shop. It was more... (oral) |
(1) | (10 mg) |
| Oxycodone Oxycodone Oxycodone is an opioid analgesic medication synthesized from opium-derived thebaine. It was developed in 1916 in Germany, as one of several new semi-synthetic opioids in an attempt to improve on the existing opioids: morphine, diacetylmorphine , and codeine.Oxycodone oral medications are generally... |
1.5–2.0 | 5.0–6.7 mg |
| Methadone Methadone Methadone is a synthetic opioid, used medically as an analgesic and a maintenance anti-addictive for use in patients with opioid dependency. It was developed in Germany in 1937... |
3-4 | 2.5-3.33 mg |
| Morphine Morphine Morphine is a potent opiate analgesic medication and is considered to be the prototypical opioid. It was first isolated in 1804 by Friedrich Sertürner, first distributed by same in 1817, and first commercially sold by Merck in 1827, which at the time was a single small chemists' shop. It was more... (IV/IM) |
4 | 2.5 mg |
| Diacetylmorphine (heroin; IV/IM) | 1.9–4.3 | 2.3–5.2 mg |
| Hydromorphone Hydromorphone Hydromorphone, a more common synonym for dihydromorphinone, commonly a hydrochloride is a very potent centrally-acting analgesic drug of the opioid class. It is a derivative of morphine, to be specific, a hydrogenated ketone thereof and, therefore, a semi-synthetic drug... |
5 | 2 mg |
| Oxymorphone Oxymorphone Oxymorphone or 14-Hydroxydihydromorphinone is a powerful semi-synthetic opioid analgesic first developed in Germany circa 1914, patented in the USA by Endo Pharmaceuticals in 1955 and introduced to the United States market in January 1959 and other countries around the same time... |
7 | 1.4 mg |
| Levorphanol Levorphanol Levorphanol is an opioid medication used to treat severe pain. It is the levorotatory stereoisomer of the synthetic morphinan and a pure opioid agonist, first described in Germany in 1948 as an orally active morphine-like analgesic... |
8 | 1.3 mg |
| Buprenorphine Buprenorphine Buprenorphine is a semi-synthetic opioid that is used... |
40 | 0.25 mg |
| Fentanyl | 50–100 | 0.1–0.2 mg |
| Sufentanyl | 500–1,000 | 10–20 μg Microgram In the metric system, a microgram is a unit of mass equal to one millionth of a gram , or 1/1000 of a milligram. It is one of the smallest units of mass commonly used... |
| Etorphine Etorphine Etorphine is a semi-synthetic opioid possessing an analgesic potency approximately 200 times that of morphine. It was first prepared in 1960 from oripavine, which does not generally occur in opium poppy extract but rather in "poppy straw" and in related plants, Papaver orientale and Papaver... 2 |
1,000–3,000 | 3.3–10 μg |
| Carfentanil Carfentanil Carfentanil or carfentanyl is an analogue of the popular synthetic opioid analgesic fentanyl, and is one of the most potent opioids known . Carfentanil was first synthesized in 1974 by a team of chemists at Janssen Pharmaceutica which included Paul Janssen... 2 |
10,000–100,000 | 0.1–1.0 μg |
1 In simple terms, analgesic "strength" in this table means how much more or less potent the indicated drug is compared to morphine. The values can be used to calculate approximately equivalent dosages of different opioids.
Because some of these compounds (for example, codeine and tramadol, but not morphine) are prodrugs, differences amongst people in their liver enzymes (such as the cytochrome P450 enzyme CYP2D6
CYP2D6
Cytochrome P450 2D6 , a member of the cytochrome P450 mixed-function oxidase system, is one of the most important enzymes involved in the metabolism of xenobiotics in the body. Also, many substances are bioactivated by CYP2D6 to form their active compounds...
) may result in a significantly altered drug effect.
2 Because of their extreme potency, etorphine, carfentanil, and other similarly powerful opiates are only used for the sedation of large animals. Sufentanil is the strongest opioid used in human medicine.