Inclusion Criteria:  Patients age 18 and older Acute Headache Initial pain score of 5 or more on a standard 11- point (0 to 10) numeric rating scale. Awake, alert, and oriented to person, place, and time  Exclusion Criteria:  altered mental status, allergy to aspirin, ketamine and rimegepant, pregnancy and breastfeeding unstable vital signs (systolic blood pressure <90 or>180 mm Hg, pulse rate <50 or >150 beats/ min, and respiration rate <10 or >30 breaths/min) inability to provide consent consumption of Aspirin or NSAID's within 6 hours of arrival to the ED or acetaminophen within 4 hours of arrival active PUD history of GI Hemorrhage history of renal and hepatic insufficiency past medical history of alcohol or drug abuse schizophrenia clinical findings concerning for acute intracranial process, acute infections process