b. For adults and children 12 years of age and older, the recommended dose of acetaminophen is 650 to 1000 mg every 4 to 6 hours as needed, not to exceed 4000 mg in 24 hours (Table 2). For extended-release acetaminophen, the dose is 1300 mg every 8 hours as needed, not to exceed 3900 mg in 24 hours. Some adult products (Extra Strength TYLENOL (acetaminophen) , TYLENOL (acetaminophen) Arthritis Extended Relief Formula) are not intended for use in children under 12 years of age.