This vestibular suppression can cause a bilateral weakness during caloric testing. Antihistamines can suppress the vestibular system and reduce dizziness. Some examples include meclizine (Antivert ®), diphenhydramine (Benadryl ®), and dimenhydrinate (Dramamine ®; Rascol et al, 1995). You should also avoid caffeine and alcohol in the 48 hours before the test, as both can affect vestibular responses. Eating a light meal beforehand is generally a good idea, since the test can cause nausea and an empty stomach can make that worse. When my appointment arrived, it came with instructions to avoid medication and alcohol for 48 hours prior to testing. This is to ensure nothing interferes with the results. The letter also advised having someone with you and not driving yourself, as the test is likely to make you dizzy. Avoid the following at least 24 hours before the test, because they can affect the results: Do not stop taking your regular medicines without first talking to your provider. You may find the cold water or air in the ear uncomfortable. You may feel your eyes scanning back and forth during nystagmus. The test involves irrigating the ears with air of varying temperatures, causing a convection current within the fluid-filled inner ears. This creates a sensation of movement, triggering a reflex called nystagmus, which is recorded through specialized goggles. If you're scheduled for an air caloric test, here are some tips to help you prepare: Avoid caffeine, alcohol, nicotine, sedating medications, antihistamines, sleep medications, antidepressants, analgesics, and pain medications for 48 hours prior to testing. Avoid the following at least 24 hours before the test, because they can affect the results: Do not stop taking your regular medicines without first talking to your provider. You may find the cold water or air in the ear uncomfortable. You may feel your eyes scanning back and forth during nystagmus. Avoid the following at least 24 hours before the test, because they can affect the results: Do not stop taking your regular medicines without first talking to your provider. You may find the cold water or air in the ear uncomfortable. You may feel your eyes scanning back and forth during nystagmus. To prevent nausea, avoid eating and drinking caffeine at least 4 hours prior to testing. While it is okay to eat, please eat light, and avoid heavily fried foods or lots of dairy products. While the test is generally safe, you may experience temporary dizziness or nausea during the process. Your healthcare provider will guide you through each step and prioritize your comfort throughout the test.