It has never been used in humans, but would be expected to produce effects similar to those of other potent opioid agonists, including strong analgesia, sedation, euphoria, constipation, itching and respiratory depression which could be harmful or fatal. Tolerance and dependence would be expected to develop rapidly based on the potency of the drug, as it is of a similar strength to the potent fentanyl analogues and so would most likely cause pronounced tachyphylaxis following repeated dosing.

Electroanalgesia is a form of analgesia, or pain relief, that uses electricity to ease pain.

The term PNT was chosen because it more accurately describes the neurophysiologic basis for PENS-induced analgesia.

This electroanalgesic modality was originally recommended as an alternative to TENS for dental analgesia.

Similarly when Ro48-6791 was compared to midazolam, it had similar efficacy, higher potency and a shorter recovery time, but produced less of a synergistic effect on opioid-induced analgesia and produced more severe side effects such as dizziness after the procedure.

For more severe crises, most patients require inpatient management for intravenous opioids; patient-controlled analgesia (PCA) devices are commonly used in this setting.

Central abdominal pain which is resistant to narcotic analgesia may be an indication of bowel infarction.

The Penthrox inhaler, manufactured and marketed by Medical Developments International (Melbourne, Victoria, Australia), is a hand-held inhaler device which can be used for the self-administration of methoxyflurane for analgesia (relief of pain).

The Penthrox inhaler is indicated for use by children and adults for the self-administration of methoxyflurane for analgesia in emergency and remote settings.

Despite the potential for renal impairment when used at anesthetic doses, no significant adverse effects have been reported in the literature when it is used at the lower doses (up to 6 millileters) used for producing analgesia and sedation.

In 1968, Robert Wexler of Abbott Laboratories developed the Analgizer, a disposable inhaler that allowed the self-administration of methoxyflurane vapor in air for analgesia.

Because of the simplicity of the Analgizer and the pharmacological characteristics of methoxyflurane, it was easy for patients to self-administer the drug and rapidly achieve a level of conscious analgesia which could be maintained and adjusted as necessary over a period of time lasting from a few minutes to several hours.

When used for labor analgesia, the Analgizer allows labor to progress normally and with no apparent adverse effect on Apgar scores.

The Analgizer was widely utilized for analgesia and sedation until the early 1970s, in a manner that foreshadowed the patient-controlled analgesia infusion pumps of today.

Dopamine is a catecholamine neurotransmitter with roles in pain perception and natural analgesia.

Metabolites for the monoamine neurotransmitters serotonin, norepinephrine, and dopamine—all of which play a role in natural analgesia—have been shown to be lower, while concentrations of endogenous opioids (i.e., endorphins and enkephalins) appear to be higher.

Methylnaltrexone (MNTX, trade name Relistor) is one of the newer agents of peripherally-acting μ-opioid antagonists that act to reverse some of the side effects of opioid drugs such as constipation without affecting analgesia or precipitating withdrawals.

Because it contains a permanently charged tetravalent nitrogen atom, it cannot cross the blood–brain barrier, and so has antagonist effects throughout the body, counteracting effects such as itching and constipation, but without affecting opioid effects in the brain such as analgesia.

However, since a significant fraction (up to 60%) of opioid analgesia can be mediated by opioid receptors on peripheral sensory neurons, particularly in inflammatory conditions such as arthritis, traumatic or surgical pain, MNTX may increase pain under such circumstances.

One of his patients, struggling with the pain of prostatic cancer that had metastasized to his bones, was now declining the morphine he required for analgesia because of constipation.

The compound looked promising and passed initial screening in which rodents were given opioids along with charcoal meals to track GI transit, and were tested for analgesia.

In a 1982 paper by Russell et al., it was first reported that the GI effects of the opioids could be prevented without affecting centrally mediated analgesia in this model.