Local anesthetics, such as lidocaine or articaine, are commonly administered before dental work or minor medical procedures to prevent pain. While effective, the temporary loss of sensation often extends long after the procedure is complete, affecting the ability to speak, drink, and eat normally. This residual numbness can lead to side effects like drooling or the inability to feel the mouth correctly.
Understanding the Duration of Numbing Agents
The length of time a local anesthetic remains active is variable, generally ranging from one to four hours for soft tissue. This duration is determined by the specific chemical properties of the agent and how the body handles it. For example, modern dental anesthetics like articaine have a shorter half-life than older agents because a significant portion is broken down in the blood plasma, leading to faster clearance.
A major factor influencing duration is the addition of a vasoconstrictor, such as epinephrine, to the solution. This substance constricts the blood vessels near the injection site, slowing the rate at which the body absorbs the drug into the bloodstream. While beneficial during a lengthy procedure, this localization extends the post-procedure numbness. The anesthetic must ultimately be metabolized by the liver or blood enzymes and then excreted, a process influenced by an individual’s metabolic rate.
Safe and Practical Methods to Encourage Recovery
The most effective way to encourage a faster return of sensation is to increase blood flow to the affected area. Increased circulation helps carry the anesthetic from the tissue into the bloodstream, where it can be metabolized more quickly. Engaging in gentle physical activity, like taking a short walk immediately after the appointment, can raise your overall heart rate and boost circulation throughout the body.
Applying a mild, external heat source to the cheek near the numb area is another practical method to increase localized blood flow. Blood vessels naturally widen in response to warmth, which accelerates the drug’s removal from the tissue. Place a warm, damp compress on the outside of the face for ten to fifteen minutes. The heat must be very mild, as the lack of sensation prevents the detection of a dangerously hot temperature, which could easily cause a burn.
Gently massaging the cheek and lips with clean fingertips can also help stimulate circulation in the immediate area. Hydration supports the body’s natural processes, including the metabolism and excretion of the anesthetic agents. Some dental offices offer a professional reversal agent, such as phentolamine mesylate, which is injected to accelerate the return of sensation, often cutting the duration of soft tissue numbness by half.
Necessary Precautions While Sensation is Impaired
While waiting for the numbing to dissipate, it is important to take specific steps to prevent accidental self-injury. The complete loss of feeling makes it easy to inadvertently bite down on the tongue, cheek, or lip without realizing it, which can cause injury and swelling. It is safest to delay eating and chewing until the sensation has returned fully to the tongue and lips.
Avoid consuming any hot liquids or foods, such as coffee, soup, or tea, during the period of numbness. The inability to register temperature accurately can lead to accidental burning of the oral tissues. Instead, stick to cool or lukewarm, soft foods and liquids that require little chewing. Young children should be monitored closely to prevent them from playing with the numb area, which can also cause tissue damage.