acetaminophen

Acetaminophen (APAP, Acetyl Para Amino Phenol) is an over the counter pain killer that has been used widely in pediatrics, adolescents, adults, and geriatrics for years as a substitute for aspirin (ASA). Unlike aspirin, acetaminophen is not contraindicated(i.e. not allowed) in the young, under twelve years of age with fever, or those either allergic to aspirin, have stomach disorders(ulcers, gastritis) or are on medications for thinning the blood (clot preventing medication). It is for mild to moderate pain of headache, toothache, menstrual cramps, muscle and arthritic pain, fever reduction, and for relief of cold symptoms, and is available in liquids, tablets, and suppositories for patient ranging from pediatrics to geriatrics and is usually a safe drug when taken in proper dose, for proper length, and with knowledge of side affects and warnings of avoidance of certain lifestyle habits.

APAP is contraindicated in patients with liver disease or a history of alcoholism and alcohol consumption must be moderate(3 or less alcoholic drinks per day while on 2 grams(2000 mg)or less of APAP daily. Patients with persistent viral flu symptoms who have stopped eating should discontinue using APAP for that period of time. Five years of persistent use of APAP along with regular ingestion of other analgesics may induce analgesic nephropathy. Generally, side effects of APAP are uncommon with "therapeutic doses" (proper doses for current problem for proper duration), however hepatotoxicity(liver disease) is possible with doses greater than 4 grams(4000 mg) per day in habitual drinkers or routinely ingest in fasting conditions.

For general everyday aches pain, the self medicating dose for adults should be 1 gram(1000mg) four times daily for 1-2 weeks, if lower doses were ineffective. It should be noted, some authorities now recommend no more than 2.5 grams per day. Although an OTC(over the counter) medication APAP may interact adversely with coumadin and increase its effects, alcohol and induced liver disease, or certain epileptic medicines-the phenytoins(Dilantin) which may both reduce the benefits of APAP and increase the risk of liver disease. Pregnant women or nursing mothers should first consult their physician prior to taking APAP since it can pass into breast milk and may harm the baby.

APAP is available for convenient dosing in tablets, capsules, suppositories, liquid, and granule form. It is important to know the concentration in any form for proper dosing, especially in the liquid form as the adult liquid versus the infant or toddlers. The infant liquid allows smaller volumes so has a higher concentration, 80mg/0.8ml (dropper dosage, 5ml/cc ==one teaspoonful)while the toddler and older children’s liquid and suspension are more dilute(160mg/5ml or cc). This means 1.6ml of the infant formulation ==5ml (one teaspoonful) of the older children’s liquid. This is a common administration error in a household with children of various ages.

Pediatric dosages are based upon age and body weight. Neonates: rectal suppository 10-15mg/kg (1kg= 2.2lbs) every 6-8 hours as needed Children: ages 2-12 years , orally 10-15mg/kg or rectally 15-20mg/kg every 4-6 hours as needed , ages >12, 325-650mg every 4-6 hours as needed up to 4 grams/day.

Many OTC medication formulations contain APAP, which must be taken into consideration for the total daily amounts as noted.

• Actifed
• Feverall
• Sinutab
• Anacin
• Formula 44
• Sudafed
• Benadryl formulations
• Goody’s Powders
• Theraflu
• Cepacol
• Liquiprin
• Triaminic
• Contac
• Midol
• Tylenol Products
• Coricidin
• Nyquil
• Vanquish
• Dayquil
• Panadol
• Vicks
• Dimetapp
• Robitussin
• Zicam
• Dristan
• St Joseph’s Aspirin-free
• Elixir
• Singlet

Many common prescription medications contain APAP

• Endocet
• Phenaphen
• Fioricet
• Sedapap
• Hycotab
• Tapanol
• Hydrocet
• Ultracet
• Lorcet
• Vicodin
• Lortab
• Zydone
• Percocet

APAP side effects include low fever with nausea, stomach pain, loss of appetite, dark urine, clay colored stools, jaundice(yellow skin or eye color) and the common signs of allergic reaction including hives, difficulty breathing, swelling of the face, lips, tongue, throat which are medical emergencies.

References

The RX Consultant, Vol XIX, Number 11, December 2010. Vol IX, Number 5, May 2000 Vol IX, Number 5, May 2002 Vol X, Number 1, January 2001

Drugs.Com/Acetaminophen Tylenol.Com/news

My personal experience with APAP as a community, hospital pharmacist and now practicing podiatrist has been very favorable in its use for mild everyday aches, pains and fever reduction. I have recommended various OTC APAP/combination containing products to the pharmacy patient for brief symptomatic relief of cough/colds/congestion and have found patients tolerate well and have gotten relief when not also accompanied by infection, in which referral to their physician was necessary.

In my daily podiatry practice of sports injuries treating sprains, strains, fractures and post operative patients, APAP as a first line analgesic with or without a NSAID (non-steroidal anti-inflammatory) and along with adjunct proper treatment has proven very beneficial. In cases where more pain was present or a complicated serious problem presented, the use of APAP and tramadol provided significant and adequate relief. My next choice, again patient- dependent is an APAP combination with a hydrocodone (semi-synthetic codeine derivative; Lorcet, Lortab, Vicodin) which has proven to be a good substitute over an APAP/oxycodone medication (Percocet, etc.)

Over the years many consumer warnings and events have occurred with APAP as with other consumer products, medications, or foods. I recall the cyanide-APAP incident of the 1980s practicing community pharmacy in Chicago while attending podiatric medical school. Today we again hear warnings of the popular APAP. The consumer is constantly bombarded with information, of ‘varied source reliability” about various products, often ‘heightened by an aggressive news media’. Any consumable, and APAP is no exception, should be used with caution and the respect if deserves. Often the belief is OTC products, oral or topical (applied the skin) are harmless, benign. All these do affect body processes, even vitamins, when used within proper guidelines for the proper indications and time frame and with no contraindications, are generally beneficial and safe. It is important to realize all the ‘meaningful helpful” friends, relatives, media, etc. should not replace the experience, education, and knowledge of the patient’s physician, who knows all abut the patient’s history and drug consumption/tolerance past experiences.

Hopefully this article has provided more insight about APAP, and that its use for you, the reader is helpful as an analgesic when needed, and may of limited need for your life!!!

ADDITIONAL REFERENCES

Drugs.com

Harvard Health

MedlinePlus

See our other pain medication discussions.