What Is Opioid-Induced Hyperalgesia?

Opioid-Induced Hyperalgesia (OIH) is an increase in pain levels and sensitivity to stimuli that can occur while taking high doses of opioid medications. This potential side effect is usually a concern for patients receiving intravenous medications at high concentrations to control severe pain. People with cancer and certain pain conditions can be at risk, and this may be considered when developing a pain management plan. Several treatment options are available.

The precise mechanisms behind opioid-induced hyperalgesia are not fully understood. As patients take higher doses of opioids, they can experience higher pain levels, requiring in turn a higher dose, which can create a self-feeding problem. In addition, patients with this side effect may experience hypersensitivity to stimuli around them, and can develop a condition called allodynia. In patients with allodynia, a stimulus that shouldn’t be unpleasant is perceived as painful.

When signs that a patient may have opioid-induced hyperalgesia start to develop, there are several options. Discontinuing the current medication is one approach, because the patient may not be benefiting from it. It may be possible to switch to a different opioid to see if the problem persists. Practitioners can also concern non-opioid medications; for example, drugs designed to treat seizures can also sometimes manage neuropathic pain and make patients more comfortable.

Another way to approach opioid-induced hyperalgesia, if the patient doesn’t respond to these measures, is to keep increasing the dose of the medication. This can be used if the patient doesn’t do well on other drugs or alternative therapies and still experiences intractable pain. Although it can make the problem even worse, the alternative could involve leaving the patient with no pain management, which could cause acute distress. Pain control can become a significant problem for patients with critical illness, as poorly managed pain can contribute to decreases in quality of life, including psychiatric complications like severe depression.

Patients using opioids for pain may be advised to periodically rotate medications to reduce the risk of developing opioid-induced hyperalgesia. This preemptive measure can also reduce the tolerance that requires higher doses over time to provide the same level of therapeutic effect. It is important to pay attention to changes in pain levels and responses to medication, as these could be indicators of complications or side effects that might need to be addressed. Working with a physician who specializes in pain management can be helpful, as this may provide access to a wider range of treatment options.