Acetaminophen: Price, Dosage & Where to Buy

Acetaminophen is an analgesic and antipyretic medicine used to temporarily relieve minor aches, pains, headache, sore throat, and fever, and to help loosen phlegm in coughs associated with colds or flu. It has been available as a generic medicine since 1 December 1986. In the United Kingdom, lower-strength acetaminophen products can be purchased from a pharmacy, while higher doses may require a prescription.

Acetaminophen reduces pain and fever through action in the central nervous system. It is thought to inhibit an enzyme involved in the production of prostaglandins, which are chemical messengers that contribute to pain signalling and the body's temperature regulation. Unlike non-steroidal anti-inflammatory medicines, acetaminophen has limited anti-inflammatory activity in peripheral tissues.

Its exact mechanism remains a subject of ongoing research, but its effects on pain perception and the hypothalamic heat-regulating centre account for its analgesic and antipyretic properties. The expectorant action in some formulations comes from additional active ingredients that help thin mucus.

Acetaminophen temporarily relieves symptoms that occur with a cold or flu, including cough due to minor throat and bronchial irritation, minor aches and pains, sore throat, and headache. It also temporarily reduces fever.

The medicine helps loosen phlegm (mucus) and thin bronchial secretions to drain bronchial tubes and make coughs more productive. Acetaminophen addresses symptoms rather than underlying causes, so it is intended for short-term relief of discomfort associated with common minor illnesses.

The label lists a wide range of strengths and forms. Oral tablets are available in 160 mg, 325 mg, 500 mg, and 650 mg. Extended-release tablets are listed as 650 mg.

Chewable tablets are listed as 80 mg and 160 mg. Liquid and suspension forms include 160 mg per 5 mL, 500 mg per 15 mL, and 650 mg per 20.3 mL. Suppositories are listed as 80 mg, 120 mg, 325 mg, and 650 mg.

Intravenous injection is listed as 10 mg per mL and 1000 mg per 100 mL. The usual adult dose is 20 mL every 4 hours for the liquid form, with a maximum of 5 doses in any 24-hour period. The label states that adults and children 12 years and over may use this dose.

Children under 12 years should not use this adult product. The label warns not to exceed 4,000 mg of acetaminophen in 24 hours.

Store acetaminophen at room temperature, away from excessive heat and moisture, to maintain quality. Liquid forms should be kept tightly closed. Suppositories may require cooler conditions as directed on the label.

Keep all forms out of reach of children. If specific storage instructions appear on the product packaging, follow those directions. Do not use the medicine past its expiry date.

If a scheduled dose is missed, it may be taken as soon as remembered, provided the maximum daily limit of 4,000 mg of acetaminophen is not exceeded and doses remain at least 4 hours apart. Because acetaminophen is used for temporary symptom relief rather than as a course of treatment, missing a dose simply means symptoms may return until the next dose.

The medicine should not be doubled up to make up for a missed dose. If uncertain, speak to a pharmacist for advice tailored to the specific product and circumstances.

The label states that individuals who are pregnant or breast-feeding should ask a health professional before use. Because acetaminophen crosses the placenta and appears in breast milk, a discussion with a doctor, midwife, or pharmacist is advised to weigh the benefits and risks for each individual situation.