Fibromyalgia

Serotonin

Serotonin is a neurotransmitter that plays a crucial role in regulating pain perception, mood, sleep, digestion, and overall well-being. People with fibromyalgia often have lower serotonin levels, which can contribute to:

• Increased pain sensitivity. → Serotonin helps regulate the transmission of pain signals in the nervous system. Low serotonin levels may lead to an exaggerated pain response.

• Mood disorders (depression and anxiety) → Serotonin is often called the "feel-good" neurotransmitter, and its deficiency is linked to depression and anxiety, both common in fibromyalgia patients.

• Sleep disturbances → Serotonin is a precursor to melatonin, the hormone that regulates sleep. Low serotonin levels can lead to poor sleep quality, which worsens fibromyalgia symptoms.

• Fatigue and brain fog → Since serotonin influences energy levels and cognitive function, a deficiency can lead to persistent tiredness and difficulty concentrating.

Scientific Evidence Linking Serotonin to Fibromyalgia

Several studies have found lower levels of serotonin in the cerebrospinal fluid and blood of fibromyalgia patients. Additionally, some fibromyalgia treatments, like Selective Serotonin Reuptake Inhibitors (SSRIs) and Serotonin-Norepinephrine Reuptake Inhibitors (SNRIs), help improve symptoms by increasing serotonin levels.

Key Findings from Research:

• Low serotonin levels are associated with increased pain perception in fibromyalgia patients.

• SSRIs (such as fluoxetine and sertraline) and SNRIs (such as duloxetine and venlafaxine) help alleviate pain and improve mood in some fibromyalgia patients by boosting serotonin levels.

• Exercise, diet, and certain supplements can naturally increase serotonin and improve fibromyalgia symptoms.

Noradrenaline

Fibromyalgia is a chronic pain condition marked by widespread musculoskeletal pain, fatigue, poor sleep, brain fog, and emotional distress. One of the key neurochemical imbalances involved in fibromyalgia is dysregulation of noradrenaline (norepinephrine), especially in the central nervous system.

How Noradrenaline Is Involved in Fibromyalgia:

Deficient Central Pain Inhibition

In a healthy nervous system, noradrenaline helps dampen pain through descending pain pathways from the brain to the spinal cord. In fibromyalgia, low levels of noradrenaline impair this natural pain-suppression system, leading to heightened pain sensitivity (central sensitization). This means that even non-painful stimuli (like touch or mild pressure) can feel painful.

Hyperactive Stress Response

Fibromyalgia patients often have a dysregulated stress response, with imbalanced levels of noradrenaline and cortisol. Chronic stress can lead to overactivation of the sympathetic nervous system, flooding the body with noradrenaline in inappropriate ways—amplifying fatigue, poor sleep, and anxiety while further disrupting pain regulation.

Linked Cognitive and Emotional Symptoms

Low noradrenaline also contributes to “fibro fog” (difficulty concentrating, memory lapses) and mood symptoms like depression or low motivation, which are common in fibromyalgia. Since noradrenaline regulates both mental alertness and pain inhibition, its imbalance creates a mix of physical and cognitive symptoms.

If you're dealing with widespread pain, chronic fatigue, brain fog, and unexplainable exhaustion, it's not all in your head. This is fibromyalgia, a real condition that is deeply connected to hormonal and nervous system dysregulation. Most people treat fibromyalgia like a pain disorder. But at its core, it’s a communication breakdown between your brain, your hormones, and your nerves. Until that miscommunication is corrected, you stay stuck in a cycle of pain, fatigue, and frustration.

Adrenaline

Adrenaline is your stress-response hormone. It helps you react in emergencies by shutting off pain temporarily. But when you're in chronic stress mode, adrenaline either stays too high (causing hyper-alertness and tension) or crashes (leading to exhaustion and hypersensitivity). Your pain sensitivity increases, your muscles stay tight, and your body feels like it’s constantly under attack — even when you’re just sitting still.

GABA

GGABA is the brain’s calming chemical. It slows down nerve activity and pain signals. GABA is typically too low, making your brain overreact to even mild sensations. You may feel pain from touch, pressure, or stress that others wouldn’t even notice. This creates the classic “amplified pain” that defines fibromyalgia.

DHEA

DHEA is your body's natural anti-inflammatory, tissue-healing hormone. It buffers you from burnout and promotes resilience. Low DHEA levels mean your body can’t repair or recover from daily stressors. Every little effort leads to soreness. Every flare-up takes longer to heal. And inflammation becomes chronic, not temporary.

Cortisol: The Master Regulator of Stress & Inflammation

Cortisol manages inflammation, energy, and your sleep-wake cycle. Cortisol often fluctuates wildly — too high at night (causing insomnia), too low in the morning (causing exhaustion). These imbalances worsen pain, prevent deep sleep, and fuel a cycle of brain fog, fatigue, and inflammatory flares.

Glutamate

Glutamate is the brain’s main excitatory neurotransmitter, responsible for activating neurons, especially in areas that regulate pain, mood, and cognition.

What Happens in Fibromyalgia?

Fibromyalgia is characterized by:

• Widespread chronic pain

• Fatigue

• Cognitive fog ("fibro fog")

• Sleep disturbances

• Heightened pain sensitivity

Glutamate Levels in Fibromyalgia

• Insula

• Cingulate cortex

• Amygdala

• Somatosensory cortex

This elevation leads to central sensitization, where the brain amplifies pain signals, even from non-painful stimuli.

How Glutamate Drives Fibro Symptoms:

Overactivation of NMDA receptors by glutamate → increases pain sensitivity (hyperalgesia)

Glutamate also worsens:

• Sleep disruption (harder to reach deep sleep stages)

• Cognitive dysfunction (mental fog, attention issues)

• Emotional distress (glutamate also affects anxiety and mood circuits)

• Impaired glial cell function reduces the brain’s ability to clear excess glutamate → creating a vicious cycle of overstimulation and pain.