Just Checking What The Difference Was With Zyrtec & Telfast.

Just checking what the difference was with Zyrtec & Telfast. My kidney levels are not as high as they should be & I read don't take Telfast if you have kidney problems. Maybe I can ask what your thoughts are with pain (not as such). But discomfort on left side of head round the ear? No dizziness. Have taken anti inflammatory but due to kidney can't take anymore. Doctor had advised to go back & see her if no better. Stress or coming from teeth/gums (no trouble with them though). Thanks.