How injection pain travels
Our skin is covered with so-called pain receptors, sensory cells that are specially equipped to act as a sort of pain detective capable of sniffing out painful stimuli. These cells are also found in the muscles. Once an injection pain is detected, they send a message along the spinal cord to the brain.
More specifically, sensory receptors in our skin send a message via nerve fibers, called A-delta and C fibers, to the spinal cord and brainstem and then onto the brain.
So, how do nerves transmit the injection pain to the brain? There are two mechanisms to transmit nerve signals. One involves the membrane of nerve cells, called neurons that transmit electrical signals to the spinal cord. The other mechanism has to do with communication between neurons. The electrical signals reach the nerve ending and cause a release of certain chemicals called neurotransmitters that reach a nearby nerve ending and initiate another signal in the next nerve.
The signal transmission within neurons is based on electrical voltage differences that exist between the inside and the outside of the nerve cell. This is generated by the uneven distribution of electrically charged particles, or ions, the most important of which are sodium (Na+), potassium (K+), chloride (Cl!), and calcium (Ca2+). When there is no signal, the nerve membrane actively pumps these ions in and out of the cell. At the outset of an injection pain signal, these ions rush across the neuron membrane through specific protein channels in the cell’s membrane. The channels “open” or “close” in response to neurotransmitters or to changes in the cell’s membrane voltage. That results in further changes in the voltage across the neuron membrane. This process then continues all the way to the next neuron located in the spinal cord.
The nerve ending then Communicates with another nerve across microscopic gaps called synaptic clefts. A neuron sending a signal releases a chemical called a neurotransmitter, which binds to a receptor on the surface of the receiving neuron.
Come to think of it. All this mechanism is there for us to feel the injection pain, which we wish we didn’t.
Luckily, there is a new device called Noodle that makes injections comfortable. Noodle is a hand-held, battery operated device that is FDA approved and numbs the skin safely, comfortably, in a few seconds, and without chemicals for self injections. It works for subcutaneous (short needle) and intramuscular (long needle) injections. No freezer needed.
Noodle is made of high-grade polypropylene resin and tested by internal and independent 3rd party bodies. During an extensive study, it was 80% effective in eliminating injection pain in a high majority. To learn more about comfortable injections, please contact us.