Opiates are powerful painkillers. Morphine, one of the oldest opiates, is still one of the most well-known painkillers in the world that we know of. Despite the efficacy of morphine, the clinical use in chronic pain is limited because tolerance against its painkilling effects slowly built up over time. This means you need more and more before pain is reduced. The biological mechanisms that are behind this so called tolerance of morphine are complex and still not entirely clear. Morphine can also be addictive. This unwanted effect together with other side effects significantly decreases the quality of life of patients with chronic pain.

Tolerance to opiates

Different factors play a role and lead to morphine tolerance. Especially the neural and so-called glial cells are playing a major role. The production of natural factors such as prostaglandins, neurotoxins, and cytokines increases. These substances cause the build-up of opiate tolerance. Besides tolerance, there is also addiction which comes into play with the use of opioids, and many more problems, if a patient uses these drugs.

For pain relief and for inhibiting inflammation, most patients choose:

  • PEA capsules produced in the Netherlands by Russell
  • PEA tablets produced in Italy by Epitech

PEA against opiate tolerance

PEA interferes with the signals in the body, induced by opiates, which might inhibit the opiate tolerance which builds up. The proof of a decreasing opiate tolerance inhibited via the influence of PEA suggests also a possible use of PEA in the case of incomplete resolution of pain. One of the major advantages of PEA is that it is an ‘endogenous’ substance which means it is not addictive and belongs to your body.

PEA capsules with a PEA-opt® quality mark are PEA formulations that – under the supervision of doctors – are clinically tested for effectiveness and safety.


Di Cesare Mannelli L, Corti F, Micheli L, Zanardelli M, Ghelardini C. Delay of morphine tolerance by palmitoylethanolamide. Biomed Res Int. 2015;2015:894732.