Hello thanks for asking from HCM for your health related queries I can understand your concern. Lyrica (Pregabalin), Cymbalta (Duloxetine) both drugs are relatively safe drugs and are free of serious side effects. Pregabalin is a good analgesic drug and the drug is infact used in headaches. Trazodon is also an antidepressant drug and is relatively safe drug. The persistent headaches you are having couldn t occur due to interactions between these medicines. Adavir is Fluticasone and the drug is one of steroid drug. The drug is not associated with headache as side effects but its inhaler formulations can cause headaches. Flexril and Lorataden both are also not the causes of headache. So if your headache is persisting then I would advise you to please consult a doctor for proper evaluation and treatment. Thanks, Hope this helps you. Take care