Palmitoylethanolamide (PEA)

PEA is a body-own fatty acid amide that has been sold as a "special food for medical purposes" in Italy and parts of Europe (under names like Normast and PeaPure) since the late 2000s. The mechanism is unusual for a supplement: PEA does not bind cannabinoid receptors directly, but acts mostly through PPAR-alpha and an "entourage effect" that slows the breakdown of anandamide while damping mast cell and microglial activation. The clinical signal is strongest in nerve compression and mixed nociceptive-neuropathic pain.

The most convincing trial is the pivotal Italian sciatica RCT pooled in Keppel Hesselink and Kopsky's 2015 review: 636 patients with low back pain and sciatic involvement, 3 weeks of um-PEA, number-needed-to-treat of 1.5 for at least 50% pain reduction. Cruccu's 2019 post-hoc analysis on the same dataset found NNTs of 1.7 for pain and 1.5 for function at 600mg/day, with the largest effect in patients with a neuropathic pain component. The Paladini 2016 pooled meta-analysis of 12 PEA studies reported about 1.04 points of additional pain reduction per 2 weeks versus control, with 81% of PEA patients reaching VAS 3 or lower by day 60 vs 41% of controls. The Artukoglu 2017 meta-analysis (10 studies, 1,298 patients) and the Scuteri 2022 systematic review (933 patients) both confirmed a statistically significant effect over placebo, though heterogeneity is high (I-squared near 99% in Scuteri) and most of the source trials are Italian and industry-linked.

Diabetic peripheral neuropathy has a smaller but cleaner signal. Schifilliti 2014 (30 patients, 300mg twice daily, 60 days) saw a highly significant reduction in pain severity and symptom scores. Pickering 2022 (Inflammopharmacology, 70 patients, 600mg/day for 8 weeks, quadruple-blind placebo-controlled in Australia) found significant improvement on the BPI-DPN and NPSI scales, plus drops in IL-6 and CRP and a modest mood benefit. This is one of the higher-quality trials in the field and was not run by the Italian pharma-grade ecosystem.

Carpal tunnel data are mixed. Conigliaro 2011 (Italian, 600 and 1200mg/day for 30 days) saw dose-dependent improvement in median nerve latency and Tinel's sign in moderate CTS. Faig-Marti 2017 (n=61, 600mg/day for 60 days, prospective randomized) found no improvement in clinical or electrophysiological parameters at the 600mg/day dose, though some functional-status scores moved. Fibromyalgia rests largely on Schweiger 2019, a 407-patient retrospective observational study (not an RCT) where um-PEA added on to standard care produced significant VAS and FIQ improvement, but 58% of patients eventually discontinued for inefficacy. Long COVID and post-COVID smell loss have early signals from PEA combined with luteolin (Di Stadio and others), all small and uncontrolled.

Practical bottom line: PEA is worth a 6-8 week trial for chronic low back pain with a sciatic component, diabetic nerve discomfort, or carpal-tunnel-style nerve compression, at 600mg/day of a micronized or Levagen+ form. The data are messier than the marketing implies, the strongest trials cluster in Italy with industry funding, and standard non-micronized PEA has poor oral absorption. Manage expectations around a 30-50% pain reduction at best; if there is nothing by week 6-8, it is unlikely to do much more.