Topical anesthetic creams, commonly called numbing creams, contain medications such as lidocaine and prilocaine that temporarily block nerve signals in the skin. These creams are often used to reduce the discomfort or pain associated with minor procedures like needle insertions, laser treatments, waxing, or tattooing. The active ingredients penetrate the outermost layer of skin to reach the sensory nerves, providing localized anesthesia without causing a loss of consciousness. Using the correct application method is necessary to ensure the cream works effectively and safely for the procedure.
Preparing the Treatment Area
Proper skin preparation is necessary for an optimal numbing effect. The application area must be thoroughly cleaned with soap and water to remove oils, dirt, or lotions. Contaminants and natural oils interfere with the cream’s ability to penetrate the skin, potentially reducing effectiveness by up to 30%. After cleaning, the area must be patted completely dry, as excess moisture also hinders absorption.
If the treatment area has dense hair growth, gently shaving is recommended to allow for direct contact between the cream and the skin surface. It is advisable to perform a patch test 24 hours in advance to check for allergic reactions to the active ingredients. This involves applying a small, pea-sized amount of cream to a one-centimeter square area on the inner forearm and observing for signs of inflammation, such as excessive redness or swelling.
Step-by-Step Application Technique
To maximize the numbing cream’s effect, apply it in a thick, visible layer rather than rubbing it in like a typical lotion. The recommended thickness is approximately 3 millimeters, which should completely cover the area without being immediately absorbed. This application method ensures a reservoir of the active ingredient remains on the surface to facilitate deeper skin penetration.
Use clean, disposable gloves during application to prevent the medication from affecting your hands. Once the thick layer is applied, cover the area with an occlusive dressing, such as plastic wrap or a specialized bandage. Occlusion creates a sealed barrier that prevents the cream from drying out and significantly enhances the absorption of the anesthetic compounds. The occlusive wrap should extend slightly past the edges of the cream to ensure the entire treated area remains sealed.
Timing, Removal, and Post-Application Care
The time required for the numbing cream to reach its full effect varies based on the cream’s concentration and the desired depth of anesthesia, typically ranging from 30 to 90 minutes. After the recommended application time, the cream should be removed immediately before the procedure begins.
Removal involves gently wiping away the excess cream and the occlusive dressing, often using a paper towel or dry gauze. Some professionals may follow this by cleansing the area with an agent like rubbing alcohol. The skin will remain numb for a period after removal, with the effect commonly lasting between one to two hours, depending on the cream’s formulation and duration of application. Following the procedure, the treated skin should be gently cleaned and can be soothed with a non-irritating moisturizer, if appropriate.
Safety Guidelines and Contraindications
Topical anesthetics are safe when used as directed, but exceeding dosage limits can lead to serious systemic toxicity. Users must strictly adhere to the maximum recommended dose, which is often specified by a total area size or an amount (e.g., 5 grams of 5% lidocaine cream on an area no larger than 600 square centimeters). Applying the cream to excessively large areas increases the risk of the anesthetic being absorbed into the bloodstream at toxic levels.
The cream should never be applied to broken skin, open wounds, or mucous membranes like the eyes, nose, or mouth, as this significantly increases the rate of systemic absorption. Signs of local anesthetic systemic toxicity (LAST) include initial symptoms such as a metallic taste in the mouth, ringing in the ears (tinnitus), or tingling around the mouth. Prolonged application beyond the recommended time, especially under occlusion, also increases the risk of adverse effects. More serious signs that require immediate medical attention include:
- Dizziness
- Blurred vision
- Slurred speech
- Seizures or irregular heart rhythms (in rare cases)