acetylsalicylic acid (ASA)
In this drug factsheet:DIN (Drug Identification Number)
|00040851 ||PMS-ASA 325 MG TABLET|
|02283670 ||PMS-ASA 80 MG TABLET|
|02283662 ||PMS-ASA 81 MG TABLET|
|02283689 ||PMS-ASA EC 80 MG ENTERIC-COATED TABLET|
|02284529 ||PMS-ASA EC 325MG ENTERIC-COATED TABLET|
|02284537 ||PMS-ASA EC 650MG ENTERIC-COATED TABLET|
How does this medication work? What will it do for me?
Acetylsalicylic acid (ASA) belongs to the group of medications called analgesics (pain relievers), antipyretics (fever reducers), anti-inflammatories (inflammation reducers), and platelet aggregation inhibitors (anticlotting agents). It works by interfering with the production of compounds in the body that cause pain, fever, inflammation, and blood clots.
Acetylsalicylic acid (ASA) is used to relieve pain, fever, and inflammation in various conditions such as lower back and neck pain, the flu, common cold, burns, menstrual pain, headache, migraines, osteoarthritis, rheumatoid arthritis, sprains and strains, nerve pain, toothache, muscle pain, bursitis (inflammation of a bursa, a fluid-filled sac located around joints and near the bones), and following surgical and dental procedures. ASA is also used for rheumatic fever in combination with other medications. In these situations, ASA is used on an as-needed basis.
Because of the antiplatelet (anticlotting) properties of ASA, it may be used under the supervision of your doctor to:
- prevent a first nonfatal heart attack in people who are at increased risk of having a heart attack as determined by their doctor (factors that increase your risk of heart attack include: smoking, high blood pressure, high cholesterol, inactive lifestyle, stress, and being overweight)
- prevent a second heart attack or stroke
- reduce the risk of "mini-stroke" or transient ischemic attack (TIA)
- reduce the clotting properties of platelets for people who have had carotid artery surgery to prevent the recurrence of TIA and for people receiving hemodialysis through a silicone rubber access
- prevent blood clots for people who have had a total hip replacement
ASA can also be used during a heart attack to reduce the risk of dying from the heart attack.
This medication may be available under multiple brand names and/or in several different forms. Any specific brand name of this medication may not be available in all of the forms or approved for all of the conditions discussed here. As well, some forms of this medication may not be used for all of the conditions discussed here.
Your doctor may have suggested this medication for conditions other than those listed in these drug information articles. If you have not discussed this with your doctor or are not sure why you are taking this medication, speak to your doctor. Do not stop taking this medication without consulting your doctor.
Do not give this medication to anyone else, even if they have the same symptoms as you do. It can be harmful for people to take this medication if their doctor has not prescribed it.
How should I use this medication?
The recommended dose of ASA for adults varies widely according to the particular condition being treated.
To treat pain or fever in adults, the recommended dose is 325 mg to 650 mg every 4 to 6 hours as needed. The maximum daily dose is 4,000 mg, unless otherwise directed by your doctor.
For adults with conditions caused by inflammation such as rheumatoid arthritis, the usual dose is 975 mg 4 to 6 times daily on a regular basis. Sometimes, higher doses may be used.
To treat migraine headache pain, the recommended adult dose is 1,000 mg at the onset of pain or symptoms.
To prevent a first nonfatal heart attack, TIA, a second heart attack, or a second stroke, the usual dose for adults is 80 mg to 325 mg once daily, depending on your doctor's instructions.
During a heart attack, the recommended ASA dose is 160 mg to 162 mg chewed or crushed. As soon as you suspect you are having a heart attack, call an ambulance and take the recommended ASA dose, providing you have no allergies or other conditions or factors that would indicate ASA is not right for you. This dose should then be continued, under your doctor's supervision, for a month to reduce the risk of a second heart attack.
To prevent blood clots after total hip replacement surgery, the recommended dose is 162 mg to 325 mg taken daily unless otherwise directed by your doctor.
For rheumatic fever, the usual dose of ASA is 80 mg per kilogram of body weight per day in divided doses.
This medication is not recommended to be used by children, teenagers, or young adults to treat fever (see the section, "Are there any other precautions or warnings for this medication?"). However, if recommended by a doctor in other circumstances such as to treat pain, the recommended dose is 10 mg to 15 mg per kilogram of body weight every 6 hours as needed to a maximum of 2,400 mg per day (ask your doctor or pharmacist to give you the correct dose if you are unsure).
When used as an anti-inflammatory, the recommended dose is 60 mg to 125 mg per kilogram of body weight daily in 4 to 6 divided doses.
Because ASA can cause stomach irritation and upset, specially coated tablets called enteric-coated are recommended when taking ASA for long periods of time. This special coating prevents the tablet from dissolving until it has passed the stomach and moved into the small intestine. This coating also means that it will take longer for the medication to take effect, so do not use enteric-coated tablets when fast relief is required. ASA should also be taken with food to prevent stomach upset. Enteric-coated medications can be taken without food.
Many things can affect the dose of medication that a person needs, such as body weight, other medical conditions, and other medications. If your doctor has recommended a dose different from the ones listed here, do not change the way you are taking the medication without talking to your doctor.
It is important that this medication be taken exactly as prescribed by your doctor. If you miss a dose, take it as soon as possible and continue with your regular schedule. If it is almost time for your next dose, skip the missed dose and continue with your regular dosing schedule. Do not take a double dose to make up for a missed one. If you are not sure what to do after missing a dose, contact your doctor or pharmacist for advice.
Store this medication at room temperature, protect it from moisture, and keep it out of the reach of children.
Do not dispose of medications in wastewater (e.g. down the sink or in the toilet) or in household garbage. Ask your pharmacist how to dispose of medications that are no longer needed or have expired.
What form(s) does this medication come in?
Each chewable, orange, round, biconvex, scored tablet, embossed "ASAPHEN 80" contains 80 mg of acetylsalicylic acid. Nonmedicinal ingredients: D&C Yellow No. 10, FD&C Red No. 40, mannitol, orange flavour, pregelatinized starch, sodium saccharin, and stearic acid
Each chewable, salmon colored, round, biconvex tablet, embossed "ASAPHEN 81" contains 81 mg of acetylsalicylic acid. Nonmedicinal ingredients: D&C Yellow No. 10, FD&C Red No. 40, mannitol, orange flavor, pregelatinized starch, sodium saccharin, and stearic acid.
Each round, biconvex, compressed white tablet contains 325 mg of acetylsalicylic acid. Nonmedicinal ingredients: croscarmellose sodium, and microcrystalline cellulose.
Each round, white, enteric-coated tablet contains 80 mg of acetylsalicylic acid. Nonmedicinal ingredients: hydrogenated soya bean oil, hydroxypropyl methylcellulose, lactose, polyethylene glycol, pregelatinized starch, and stearic acid.
Each round, brown, enteric-coated tablet contains 325 mg of acetylsalicylic acid. Nonmedicinal ingredients: microcrystalline cellulose, guar gum, cornstarch, hydrogenated vegetable oil type I, sodium lauryl sulphate, purified water, methacrylic acid copolymer type C, talc, titanium dioxide, triethyl citrate, colloidal anhydrous silica, sodium bicarbonate, polyethyleneglycol sorbitan tristearate, polydimethylsiloxane, methylated silica, methylcellulose, polyvinyl alcohol, polyethylene glycol, FD&C Yellow No. 6 Aluminium Lake, FD&C Red No. 40 Aluminium Lake, lecithin, and FD&C Blue No. 1 Aluminium Lake.
Each oval, orange, enteric-coated tablet contains 650 mg of acetylsalicylic acid. Nonmedicinal ingredients: microcrystalline cellulose, guar gum, cornstarch, hydrogenated vegetable oil type I, sodium lauryl sulphate, purified water, methacrylic acid copolymer type C, talc, titanium dioxide, triethyl citrate, colloidal anhydrous silica, sodium bicarbonate, polyethylene glycol sorbitan tristearate, polydimethylsiloxane, methylated silica, methylcellulose, polyvinyl alcohol, polyethylene glycol, FD&C Yellow No. 6 Aluminium Lake, and lecithin.
Who should NOT take this medication?
Do not take acetylsalicylic acid if you:
- are allergic to ASA or any ingredients of the medication
- are in your last trimester of pregnancy
- are prone to bleeding
- are using methotrexate at doses of 15 mg or more per week
- have an active gastric ulcer
- have had a severe allergic or asthmatic reaction caused by salicylates, ASA, or nonsteroidal anti-inflammatory drugs (NSAIDs; e.g., diclofenac, ibuprofen, indomethacin, naproxen)
- have severe kidney failure
- have severe liver failure
- have severe congestive heart failure