The present invention is directed to dosage forms that can be used in therapeutic methods involving the oral co-administration of a combination of at least two drugs, one of which impairs gastrointestinal absorption and one of which does not. The dosage forms are designed so that the drug impairing absorption is not released into the gastrointestinal tract of a patient until after the drugs that do not impair absorption have been released and substantially absorbed. The invention may be used in treatment of migraine using a combination of triptans and NSAIDs or in the treatment of pain using a combination of NSAIDs and opioid analgesics.