CN IX and X – Glossopharyngeal and Vagus Nerve

1. To test taste related to CN IX, use the same steps as step 3 in the previous section related to CN VII, except introduce the substance to the posterior third of the tongue. This test is only done when there are specific concerns.
2. To test gag reflex as related to CN IX and CN X, use a tongue depressor to tap near the lateral side of the pharynx near the tonsillar pillars or at the lateral posterior side of the soft palate. While doing this, use a penlight to illuminate the inside of the mouth and pharynx. Test on both sides of the mouth. See Video 14.
   • Normally the client will gag, meaning that the pharynx will constrict/contract and the uvula and midline of the soft palate will move upward.
   • Abnormal findings include an absent or decreased gag reflex, as well as an overactive gag reflex.
3. Next, ask the client to open their mouth and inspect the soft palate and uvula, and then have the client stick out their tongue and say “ahh.”
   • Normally the soft palate is symmetrical and uvula is midline. When they say “ahh,” the soft palate should elevate and the uvula should elevate while remaining midline.
   • Abnormal findings include an asymmetrical palate, a deviating uvula, and a palate that does not move upward.
4. You may ask the client to swallow, or to take a sip of water and swallow, to ensure they have no difficulty swallowing.
5. Throughout this assessment, continually listen to the client’s speech to ensure there is no hoarseness or difficult speaking.
6. Note the findings:
   • Normal findings might be documented as: “Gag reflex present, soft palate and uvula symmetrical and mobile with no dysphagia, dysphasia or hoarseness.”
   • Abnormal findings might be documented as: “Gag reflex absent. Client unable to clearly form words.”

Gag reflex link (from kaltura)

Video 14: Gag reflex