Why did my tongue and mouth become temporarily numb when I bit into my Elavil pill to cut it in half?

When you bite into a pill, especially one like Elavil, it can cause temporary numbness in your tongue and mouth. This is because the medication can have a local effect on nerve transmission, leading to the sensations of numbness you experienced. It is not uncommon for medication like this to be used in compounding creams for pain relief in cases of nerve pain. In the future, it is recommended to use a pill cutter to safely split pills. Your pharmacy can provide you with one or even cut the pills for you if needed.