Why Withdrawal Symptoms Feel So Intense

Article 1 of the Withdrawal Symptoms series

How changes in inhibitory stability during benzodiazepine withdrawal can activate stress-responsive systems and increase physiologic signaling throughout the body.

Recognizing the Experience

People who reduce or stop benzodiazepines are often surprised by how intense withdrawal symptoms can feel. Sensations such as palpitations, dizziness, muscle tension, internal vibrations, breathing discomfort, or sensory sensitivity may appear suddenly and feel difficult to ignore.

These experiences can be alarming, particularly when medical tests do not identify a clear disease process. Many individuals understandably wonder why their bodies seem to be producing such strong sensations.

Understanding these symptoms begins with examining how the nervous system normally maintains physiologic stability.

Inhibitory Balance in the Nervous System

Benzodiazepines act primarily by enhancing signaling through the inhibitory neurotransmitter gamma-aminobutyric acid (GABA). GABA plays an important role in stabilizing neural circuits and preventing excessive neural activity.¹

When benzodiazepines are used over extended periods, the nervous system gradually adapts to this enhanced inhibition. Neural circuits adjust receptor sensitivity and signaling balance so that overall activity can remain relatively stable.²

However, when the medication is reduced or discontinued, this balance temporarily shifts. Neural circuits that adapted to enhanced inhibition must adjust to a new regulatory environment, and during this transition inhibitory stability may be overall temporarily reduced.

Reduced inhibitory stability does not indicate brain damage. Instead, it reflects the nervous system adapting to a change in its signaling environment.

Activation of Stress-Responsive Systems

When inhibitory stability decreases, brain circuits that regulate stress responses and physiologic regulation may show increased activity.³

These circuits help coordinate arousal, vigilance, autonomic regulation, and the body’s responses to signals arising from internal organs and tissues.⁴

When activity in these circuits increases, it can alter body processes such as heart rate, breathing, and muscle tone, generating stronger physiologic signals from organs and tissues throughout the body.

Physiologic Signals in the Body

The body constantly produces physiologic signals as part of normal regulation. Changes in heart rate, breathing, muscle activity, and sensory feedback occur continuously as the body maintains internal balance.

When regulatory systems become more reactive, these signals may become more noticeable.

For example, changes in cardiovascular regulation may produce palpitations. Increased muscle activity may generate sensations of tension or vibration. Changes in respiratory control may produce sensations of air hunger.

These signals originate within normal physiologic systems, even though the sensations they produce may feel unfamiliar or intense.

The Five-Axis Stress Biology Framework™

The Five-Axis Stress Biology Framework™ provides a way to understand how different regulatory systems interact during withdrawal. These interacting physiologic processes can be organized into five major regulatory systems within the brain and body.

Axis 1 involves neural circuits that evaluate stress and coordinate adaptive responses to internal and external signals.

Axis 2 involves the balance between excitatory and inhibitory signaling within neural networks.

Axis 3 involves autonomic regulation of the cardiovascular, respiratory, and digestive systems.

Axis 4 involves motor systems that influence muscle tone and movement.

Axis 5 involves immune signaling that interacts with neural regulation.

Activation across these interacting systems can increase physiologic signaling throughout the body. These signals form the foundation for the processes explored in the following articles in this series, including how signals are sensed, interpreted, amplified, and eventually stabilized during recovery.

From Physiologic Signals to Symptoms

Signals generated within body systems travel to the brain through specialized sensory pathways that continuously inform the brain about the body’s internal state.⁵ 

Signals from internal organs are transmitted primarily via vagal sensory fibers, whereas signals from muscles and other tissues travel via spinal sensory pathways. These signals first reach integration centers in the brainstem before being relayed to higher brain regions that monitor the body’s internal state.

Brain networks responsible for monitoring internal conditions interpret these signals and determine whether they require attention. Cortical regions such as the insula and anterior cingulate cortex play important roles in this process by evaluating incoming signals and helping determine whether they enter conscious awareness.

When physiologic signals become stronger or more frequent, the brain may register them as noticeable sensations. These sensations are experienced as symptoms. Understanding symptoms as the brain’s interpretation of physiologic signals helps explain why they can feel intense even when medical testing does not reveal structural disease.

Diagram

Figure 1. Conceptual model of withdrawal symptom formation.

Changes in inhibitory stability during benzodiazepine withdrawal can activate multiple stress-responsive regulatory systems, increasing physiologic signaling throughout the body. Signals traveling to the brain may then be interpreted as symptoms.

Looking Ahead

This explanation raises an important question: if symptoms arise from signals generated in the body, how does the brain sense and monitor those signals?

In the next article, we will examine the neural pathways that allow the brain to monitor internal body signals through a process known as interoception.

Selected Scientific References

1. Nutt DJ, Malizia AL. New insights into the role of the GABA(A)–benzodiazepine receptor in psychiatric disorder. Br J Psychiatry. 2001;179:390–396.

2. Lader M. Benzodiazepines revisited—will we ever learn? Addiction. 2011;106(12):2086–2109.

3. Ulrich-Lai YM, Herman JP. Neural regulation of endocrine and autonomic stress responses. Nat Rev Neurosci. 2009;10(6):397–409.

4. Benarroch EE. The central autonomic network: functional organization, dysfunction, and perspective. Neurology. 1993;43(10):1993–2000.

5. Critchley HD, Harrison NA. Visceral influences on brain and behavior. Neuron. 2013;77(4):624–638.