What is the Vagus Nerve?
The vagus nerve, the 10th cranial nerve, is a crucial part of the parasympathetic nervous system, responsible for involuntary functions like breathing, digestion, hunger, blood pressure, and heart rate. Additionally, it significantly influences mood regulation, inflammation, and immune responses. The vagus nerve can be stimulated with electrical impulses to enhance and support the overall function of the nerve which can be beneficial for treating various medical conditions. This form of stimulation is commonly known as Cranial Electrical Stimulation (CES), Transcutaneous Vagus Nerve Stimulation (tVNS), Transcutaneous Auricular Vagus Nerve Stimulation (tAVNS), or, simply, Vagus Nerve Stimulation (VNS). This therapy is commonly used to help treat conditions such as epilepsy, tinnitus, depression, inflammatory diseases, and much more.
What is a TENS unit?
A Transcutaneous Electrical Nerve Stimulator (TENS) unit is a safe, noninvasive, compact device that delivers low voltage therapeutic electrical impulses to the skin and nerves. These impulses help manage pain by blocking pain signals from reaching the brain and stimulating the body's natural painkillers, called endorphins. The electrical impulses are distributed through self-adhesive pads that target specific nerve endings.
To perform a treatment, the unit requires specific settings for frequency (Hz), pulse duration (µs), and intensity (mA). A single session can last anywhere between 10 to 60 minutes as directed by your doctor. TENS is recommended for multiple conditions, including:
Arthritis
Acute Pain
Chronic Pain
Fibromyalgia
Neuropathy
Muscle Tension/Spasms
Sports Injuries
Postoperative Pain
What is a Microcurrent Unit?
A Microcurrent unit is a noninvasive electrotherapy device that delivers low-level sub-sensory impulses to stimulate muscles and tissues. This helps alleviate pain and promote healing in the body. These impulses are distributed through self adhesive pads that stimulate adenosine triphosphate (ATP) production, enhancing physiological functions such as nervous system signaling, muscle development, and tissue reconstruction.
The unit requires a set frequency (Hz), pulse duration (ms) and intensity (mA) to perform a treatment. A single session can last between 20 minutes to an hour as directed by a healthcare physician. Microcurrent is recommended for multiple conditions and symptoms, such as:
Soft-Tissue & Wound Healing
Scar Tissue Breakdown
Fibromyalgia
Stress/Anxiety
Inflammation
Swelling
Neuropathy
Neuralgia
Transcutaneous Auricular Vagus Nerve Stimulation & Electrotherapy
TENS and Microcurrent are the two most commonly recommended waveforms for stimulating the vagus nerve. Electrical impulses from the device are delivered through the skin using an ear clip electrode on the left ear. The two most common sites for electrode application are the tragus and/or cymba conchae. The left ear is preferred because the right ear has a greater interference with the heart, as the right side of the vagus nerve innervates the SA node, which can slow down the heart. These impulses travel through the auricular nerve of the ear, connecting to the vagus nerve and reaching the brainstem. This process releases neurotransmitters into various areas of the brain, promoting neuroplasticity. Consistent stimulation leads to structural and functional changes, helping to create new neural pathways that result in a more regulated nervous system.
Common parameters include frequencies from 1 Hz to 100 Hz, with most studies focusing on the 1-10 Hz range or up to 100 Hz for varying effects. Pulse widths are typically between 100 to 500 microseconds, often around 200-300 microseconds. The intensity is adjusted for patient comfort, usually between 0.1 mA to 5 mA, with many studies using 1-2 mA to create a slight tingling sensation without causing pain. Sessions generally last from 15 minutes to an hour and can be conducted once daily or several times a week. For specific applications and personalized settings, it's essential to consult with a trained professional who can tailor the therapy to individual needs and ensure safe and effective treatment. For more detailed information and guidance on tAVNS, it is important to reach out to a healthcare provider.
Benefits & Indications of Vagus Nerve Stimulation
Research has shown that vagus nerve stimulation therapy offers many benefits, including:
Lowering Blood Pressure
Promoting Calmness and Relaxation
Minimizing Seizures in those with Epilepsy
Improving Sleep
Enhancing Cognitive Function
Reducing Inflammation
Improving Digestive Function
Enhancing Quality of Life
Reducing Symptoms of Depression & Anxiety
Vagus Nerve Stimulation is commonly used to treat a variety of conditions, including:
Depression
Tinnitus
Epilepsy
Migraine
Anxiety Disorders
Cognitive Disorders
Post-Traumatic Stress Disorder (PTSD)
Irritable Bowel Syndrome (IBS)
Chronic Fatigue Syndrome (CFS)
Postural Orthostatic Tachycardia Syndrome (POTS)
Specialized Stimulation Devices vs. TENS Pros TENS & Microcurrent Units for Transcutaneous Auricular Vagus Nerve Stimulation
In the realm of vagus nerve stimulation, several devices have gained popularity over the years, including Truvaga, Pulsetto, Apollo Neuro, and gammaCore. Each offers unique features, but when considering cost, availability, and effectiveness, our longtime preferred go-to devices - the InTENSity Select Combo and InTENSity Micro Combo - truly stand out.
Truvaga ($299) and Pulsetto ($499) provide non-invasive VNS options but often come with higher price tags and limited availability. Apollo Neuro ($309) focuses on wearable technology for stress relief, while gammaCore offers a prescription-only device primarily for headache treatment.
In contrast, the InTENSity Select Combo and InTENSity Micro Combo are not only more affordable but also widely accessible. What sets these devices apart is their versatility; they allow users to set specific custom electrotherapy treatment parameters (Waveform, Pulse Width, Pulse Rate, etc.) tailored to their individual needs, ensuring more personalized and effective therapy. With superior customization options and a user-friendly design, these units provide a comprehensive solution for VNS, and other common electrotherapy applications, making them the top choice for those seeking efficient and adaptable treatment options.
Side Effects & Contraindications
When considering TENS and Microcurrent therapy for vagus nerve stimulation, it's important to be aware that while these treatments are generally considered safe, they can come with some side effects and contraindications. Common side effects include skin irritation, redness, and discomfort at the electrode sites. Some individuals may also experience headaches, dizziness, vocal hoarseness, nasopharyngitis, or muscle twitching.
It's crucial to note that TENS and Microcurrent therapy should not be used by individuals with implanted electronic devices such as pacemakers or defibrillators, as the electrical impulses may interfere with these devices. Always consult with a healthcare professional before starting any new treatment to ensure it is safe and appropriate for your specific health needs.
References:
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Barbanti, P., Grazzi, L., Egeo, G., Maria Padovan, A., Liebler, E., and Bussone, G. (2015). Non-invasive vagus nerve stimulation for acute treatment of high-frequency and chronic migraine: an open-label study. J. Headache Pain 16:61.
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