Is doxycycline well tolerated, & is it one of the antiobios more likely to cause allergic reactions? i'm allergic to keflex and nervous to take doxy.

Doxycycline: Doxycycline can sometimes cause stomach upset, and this can potentially limit its use. This side effect is not an allergy, however. People who are allergic to Keflex (generic cephalexin) may need to avoid other so-called beta-lactam antibiotics, which include the penicillins and cephalosporins. An allergy to Keflex would not predispose you to an allergy to Doxycycline as they are not related.

Unusual: Doxycycline allergy is rare but you may be more prone to get a sunburn while on it. Keflex is not related to Doxycycline and the allergy (if it is a real one other than a rash) is likely specific to Keflex although penicillin allergy should be ruled out. However, people allergic to penicillin is not usually allergic to keflex. See an allergist if you need more clarifications.