Duplication or reproduction of existing classified information is not derivative classification. Persons who apply classification markings derived from source material or as directed by a classification guide need not possess original classification authority. (b) Responsibility.
According to my doctor, 4 hours. You can switch them up. Take acetaminophen, (Tylenol), then wait 4 hours and take Ibuprofen, wait another 4 hours and take acetaminophen and so on. :) 15 people found this useful.
Take only the recommended dose of Tylenol, and do not take it with other medicines containing acetaminophen. In rare cases, an overdose of acetaminophen can cause liver failure and death. Wait another four hours. After eight hours from your first dose of ibuprofen, take another dose of ibuprofen.