Lidocaine Ointment USP 5% is a topical medication that provides localized numbness and temporary relief from various types of discomfort. Applied directly to the skin, its active ingredient reduces sensations of pain or itching. It offers a convenient way to manage superficial discomfort.
Understanding Lidocaine Ointment USP 5%
Lidocaine Ointment USP 5% contains lidocaine, a local anesthetic from the amino amide class. The “USP” designation indicates the product meets United States Pharmacopeia standards for quality, purity, and strength. The “5%” refers to a concentration of 5 grams of lidocaine per 100 grams of ointment.
Lidocaine works by stabilizing neuronal membranes, inhibiting the ion movements necessary for nerve impulses. This action primarily involves blocking sodium ion channels on nerve cell membranes. By preventing these signals from reaching the brain, lidocaine creates a numbing sensation, reducing pain or discomfort. When applied topically, the numbing effect typically begins within 3 to 5 minutes.
Common Applications
Lidocaine Ointment USP 5% is commonly used for temporary relief of pain and discomfort stemming from various minor skin irritations. It can soothe the stinging and aching associated with minor burns, including sunburn, and helps alleviate the itching and irritation from insect bites. The ointment is also beneficial for skin abrasions and minor cuts. For those experiencing reactions to plants like poison ivy, poison oak, or poison sumac, lidocaine ointment can help reduce the associated itching and discomfort.
Beyond these general skin irritations, the ointment also addresses specific conditions such as the pain and itching from hemorrhoids. Additionally, it serves a role in numbing accessible mucous membranes, such as those in the mouth or throat, for certain medical or dental procedures. For instance, it can be applied to prepare the area for intubation or to ease discomfort during denture fitting. Its numbing properties are also utilized to minimize pain before minor medical procedures, including injections, intravenous (IV) line insertions, or skin biopsies.
Proper Application and Safety
Applying Lidocaine Ointment USP 5% correctly is important for effectiveness and safety. Before application, the skin should be clean and dry. Apply a thin layer to the affected area, using only the smallest amount necessary for relief. For broken or burned skin, a sterile gauze pad may be used. Wash hands thoroughly after applying the ointment, unless the hands are the area being treated.
The ointment should not be applied to large areas of the body or to severely broken, irritated, or blistered skin, as this can increase systemic absorption. Covering the treated area with bandages, plastic wrap, or heat can also enhance absorption and should be avoided unless specifically instructed by a healthcare professional. Apply three to four times a day, not exceeding 5 grams (approximately 6 inches from the tube) in a single instance.
While safe when used as directed, Lidocaine Ointment USP 5% can cause mild side effects such as temporary irritation, redness, stinging, or itching at the application site. Accidental numbness in unintended areas can also occur. More serious, though rare, side effects include allergic reactions like hives or swelling of the face, lips, or throat. A serious blood condition called methemoglobinemia, characterized by pale, gray, or blue-colored skin, headache, or shortness of breath, is a rare side effect. Seek medical attention promptly if symptoms worsen, persist, or if any severe reactions occur. Keep the ointment out of reach of children; it is not recommended for use on infants for teething pain.