What Is Opioid Potency?

Opioid potency measures how much of an analgesic medication is needed to produce a painkilling effect. Morphine is often used as the standard of reference for this measurement. Charts are available to show care providers how much of a given painkiller, like tramadol, would be needed to achieve the effect of a standardized morphine dose, like 10 milligrams taken orally. When making decisions about what to recommend for a patient, available drugs and pain levels are considered to decide which medication would be appropriate.

These compounds have been used in pain management for centuries, and a range of them are produced, including very powerful synthetics. Effects can vary both depending on the medication and how it is delivered. Oral medications need higher doses to be effective in contrast with those delivered directly into the bloodstream. In addition, patients with liver dysfunction may process the medication differently, and thus achieve different levels of pain control. Developing opioid potency equivalency charts allows medical professionals to determine which drug to use when, and in what dosage.

Some examples of medications with a lower opioid potency, ranking below morphine in terms of strength, include codeine and aspirin. Stronger medications like fentanyl and methadone are also available. Medical professionals deciding what to recommend needs to think about effective pain control to keep a patient’s baseline levels reasonable, and may also want to consider the risk of breakthrough pain. Patients with this type of pain can experience sudden spikes that require a fast-acting analgesic with a higher opioid potency.

Medical professionals may want to keep patients on a low strength opioid for as long as possible. This can reduce the risk of side effects and help the patient retain mental clarity while receiving pain control. In some cases it may be necessary to switch due to rising pain levels, the development of tolerance, or a change in the patient’s condition; for example, someone might not be able to take oral medication anymore, and needs to switch to a patch or intravenous delivery method.

When switching between pain management medications, opioid potency is an important consideration. A patient who has been taking codeine for pain couldn’t make the jump to fentanyl, a much more powerful medication, without careful monitoring, for example. The dosage may require several careful adjustments to find an effective level for the patient. Analgesics can also be combined to control both chronic and breakthrough pain; cancer patients, for example, may need fast-acting opioids in addition to ongoing pain management.