Now, I'm wondering if Synthroid could be causing my severe nervous condition or anxiety. While on Levo, with abnormal labs, I never once felt this type of horrendous nervous condtion, even when I was super hyper. Condition started again tonight, approx 2 hours after I took Synthoid. I'm on 162 dose, 150/175 split, when I take 175 dose, I have panic attacks. Been paying attention lately, after taking Synthroid. Appears my body is sensitive to ever synthetic med.