What is the active ingredient in aspirin?
The active ingredient in aspirin is acetyl-salicylic acid.
How does aspirin work?
COX also plays a role in cessation of bleeding. Blood clotting is the result of a complex mechanism which involves many different cells, including a type of blood cell known as platelets. When blood vessels are damaged or are diseased, platelets clump together to facilitate repair. COX activates a chemical known as thromboxane A2 that causes platelets to stick together to form a ‘plug’ over the damaged area. The aggregation of platelets (forming a platelet plug), in concert with the clotting process, results in a fibrin clot which stops bleeding and aids repair of the blood vessel. Aspirin inhibits COX and reduces the ability of the platelets to form a plug. This is why aspirin is known as a ‘blood thinner’ or anti-platelet agent.
What is the reason for using only a 100mg dosage in the trial?
This is a dose that has blood thinning (anti-platelet) actions with low side effects from bleeding. This dose is lower than that usually taken for pain relief and for reducing fever. It is the same dose prescribed for people who need aspirin for secondary prevention, e.g. to prevent a second heart attack or stroke.
Are there any risks with taking aspirin?
Some prostaglandins cause fever, inflammation and pain, while other prostaglandins form a layer on the stomach wall to protect it from harsh stomach acid. Aspirin inhibits the production of prostaglandins, which will reduce fever, pain and inflammation, but it will also put the stomach at risk of this layer thinning. If the layer becomes too thin stomach acid can erode the wall of the stomach and form an ulcer.
Others side effects of aspirin are related to its action on platelets. Aspirin’s anti-platelet or blood thinning effect leads to a delay in blood clotting. This means that if you bleed and are taking aspirin, the bleeding may take longer to stop. Symptoms of this longer bleeding time may include bruises, blood in the stools (due to gastrointestinal bleeding), or in the worst case, a bleed into the brain (cerebral haemorrhage or a bleeding stroke). These adverse effects are risks. Although some people unfortunately experience side-effects, not everyone that takes aspirin will experiences adverse effects.
ASPREE is the first study in the world to determine the balance of the benefit of aspirin versus the risk of side-effects in healthy older people.
What are the long term effects of taking aspirin?
Prolonged use of aspirin at higher doses can cause stomach ulcers, and can also prolong bleeding time. The low-dose form of aspirin (100mg) used in the ASPREE study reduced the risk of developing stomach ulcers from aspirin, while also having the potential to provide therapeutic benefit. ASPREE is the first study in the world to determine the balance of potential benefit versus the risk of aspirin for primary prevention of disease.
The ASPREE Clinical Trial finished in December 2017.
ASPREE-XT (eXTension) is a follow up observational study of possible long term effects of aspirin in older people, which commenced in January 2018. There are indications that taking aspirin for a period of time may reduce the incidence and spread of some cancers, such as bowel cancer, however this may not be evident until may years later.
Will 100mg of aspirin cause tinnitus (ringing in the ears)?
Does aspirin react with other drugs?
Aspirin belongs to a class of drugs called non-steroidal anti-inflammatory drugs (NSAIDs). If you take a number of NSAIDs at the same time the side effects can be cumulative. For this reason, if you are taking regular NSAIDs we ask you to speak with your GP about their use and potential alternatives.