There are many numbing creams available in the marketplace. Some of these numbing creams can be found in pharmacies, doctor’s offices, hospitals and online. The differences among competitive products that make one better than others is due to formulation and the other packaging. In terms of formulation, one leading consideration is to supply a fast acting numbing cream. Once a numbing (anesthetic) agent is in the skin, the mechanism of action is the same among the common active pharmaceutical ingredients (API’s). The API blocks neuronal impulses of pain from the localized area to the brain.
What makes one product a fast acting numbing cream is its distinct formulation. Any marketer of topical products can call its product a fast acting numbing cream. However, for this to be true, the formulators need to make sure that one or more of the following ingredients that temporarily increase permeability of skin are included:
These ingredients, singly, or in combination, are known to speed the delivery of API’s into the skin, which can in turn, help in creating and supplying a fast acting numbing cream. One of the ingredients, DMSO is also know to deliver API’s directly into the blood stream. With many API’s this can lead to safety risks due to cumulative systemic absorption that can lead to toxicity. Limiting the amount of API entering the blood should also be a goal of those making and supplying a fast acting numbing cream.
The mechanism of action of the standard API’s found in a fast acting numbing cream is blockage of the high voltage sodium ion channel of the neuronal process. Lidocaine, found in fast acting numbing cream products, enters into the channel and blocks sodium from entering. When sodium enters, the channel is depolarized, which leads to the signal of pain. When the lidocaine (benzocaine, tetracaine, prilocaine or related) enter the sodium ion channel, they block this effect, leading to the rapid onset numbing cream effect.