Neurotransmitter Imbalance in Tension-Type Headache: A Systematic Review of Mechanisms and Therapeutic Targets.

Pain Ther · 2025 · PMC12279646 · PMID 40588693

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a possible trendno p-value reported

Regarding endogenous opioids, β-endorphins shows a possible trend toward reduced levels in both plasma and PBMCs of patients with TTH evaluated outside headache periods [ 7 , 17 , 18 , 22 ].

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