Side-effects of aspirin usage

Not all individuals who use aspirin will experience side-effects. The risk of side-effects does appear to depend on dosages, whether or not a person is taking multiple types of medications at the same time and a personal susceptibility or physical sensitivity to aspirin.

The nature of side-effects experienced may thus vary from one person to the next. In general, the very young (children and babies) or elderly are more susceptible to adverse effects. This is typically expected, no matter the type of medication being taken.

The way a child’s body absorbs, metabolises and expels substances does differ from that of the more matured, regulated body of an adult. Medication tends to absorb at a slower rate from the stomach than adults. Intramuscular absorption tends to occur at a faster rate, however. Young children also have a higher body water ratio (to lipids). Liver enzymes and kidney function mature as a young child grows too. The blood-brain barrier of a child is also more permeable than adults. 

Senior adults are also more susceptible to reactions, especially if they are already under treatment for various age-related conditions. The use of multiple medications can take its toll on an aging body. Many seniors are more likely to be taking medications that have a narrow margin between efficacy and toxicity, which increases the risk of interactions or side-effect complications. Generally prescribing doctors can help to manage such treatment conditions. Older bodies also tend to hold more fat than water which can have an impact on the effectiveness of certain medications. Metabolism and excretion of medications via the liver and kidneys does tend to slow down somewhat too. Seniors are typically more sensitive to the sedating effects of certain drugs. Pre-existing cognitive problems can sometimes worsen when on certain medications too.

For some individuals, adverse experiences may be minor (if at all), others may be more prone to more severe side-effects. In the case of minor reactions, these can often ease as the body adjusts to taking regular doses of aspirin. If this does not ease, a doctor can assist with recommendations during a medical consultation to try and alleviate any degree of discomfort experienced. Recommended advice can help to reduce particular side-effects or avert them altogether.

Should side-effects be particularly unmanageable or persistent, it is best to consult a medical doctor for a thorough evaluation and treatment recommendation. Side-effects are generally less severe when aspirin is taken at lower dosages. Sometimes an adjustment in this regard for more regular dosing may be helpful in alleviating side-effects. A medical doctor, however should make this call on a patient’s behalf, and not the other way around.

Common side-effects associated with orally taken aspirin include:

• Heartburn (or indigestion – dyspepsia)
• Stomach discomfort or pain
• An upset stomach - nausea and vomiting
• Increased bleeding tendencies – a tendency to be more susceptible to bleeding if injured (bleeding injuries may take longer to stop) or bruise easily
• Rectal irritation, pain or bleeding (this is associated with suppository use)

To manage such side-effects, adhering to the directions of use on the label or the express recommendations of a medical doctor may help alleviate discomfort. For instance, not taking this medication on an empty stomach can help reduce irritation of the stomach lining, resulting in gastrointestinal discomfort. If regular dosing is required, stomach irritation and indigestion can be further reduced by limiting certain foods such as tomatoes, or those that are fatty or greasy, as well as coffee, carbonated beverages and alcohol. Smoking may also aggravate the body and contribute to increased risk of inflammation and bleeding. Reduced dosages may be helpful too.

If nausea and vomiting are problematic, slowly drinking clear, cold liquids (water) can help. Bland foods and smaller more frequent portions (instead of large meals) while recovering from a round of nausea and/or vomiting are best. Anti-nausea medications can also be recommended by a medical doctor or pharmacist.

Bleeding injuries are likely to take longer to stop. Applied pressure will help to slow down any bleeding. Should bleeding not slow down or stop after at least 15 minutes, it is best to seek medical treatment and advise aspirin use – and other medications too if relevant, especially NSAIDs or steroids. 

Side-effects which may occur, but are considered rare or uncommon include:

• Agranulocytosis (reduced white blood cell count)
• Anaphylactic reactions
• Aplastic anaemia (a dysfunction whereby the body does not produce a sufficient amount of red blood cells)
• Erythema multiforme (formation of bull’s eye shaped lesions on the skin)
• Erythema nodosum (painful and tender bump formations beneath the skin)
• Haemorrhagic vasculitis (blood vessel inflammation)
• Lyell's syndrome (severe skin reaction, also known as toxic epidermal necrolysis)
• Menorrhagia (abnormally heavy bleeding during monthly menstruation – women) or unusual spotting / bleeding
• Shock
• Steven-Johnson syndrome (severe disorder affecting the skin and mucous membranes involving flu-like symptoms, a skin rash and the formation of blisters)
• Thrombocytopenia (low blood platelet count)

Reported side-effects which have not been defined with regards to frequency (i.e. may or may not occur – but are associated with aspirin use) include:

• Abnormal heartbeat (dysrhythmia)
• Agitation
• Altered state of consciousness
• Anaemia (iron-deficiency anaemia)
• Angioedema (swelling)
• Antepartum (before childbirth) and postpartum (after childbirth) bleeding
• Anxiety
• Asthma / asthma attack
• Belching
• Black or tarry stools or faeces (melena)
• Bleeding gums (gingival bleeding)
• Bloody, dark or cloudy urine
• Bronchospasm (narrowing of the bronchi)
• Cerebral oedema (accumulation of water within the intracellular and/or extracellular spaces in the brain)
• Chest pain or discomfort
• Coagulopathy (prolonged or excessive bleeding)
• Confusion
• Constipation
• Dehydration
• Disseminated intravascular coagulation (formation of small blood clots throughout the bloodstream, resulting in blockages within small blood vessels)
• Dizziness
• Dry mouth
• Elevations of hepatic enzymes (transient)
• Fainting
• Fever
• Gastric irritation
• Gastritis
• Gastrointestinal bleeding
• Gastrointestinal ulceration or gastrointestinal erosions
• Headache
• Hearing loss or hearing disturbances
• Hepatitis
• Hepatotoxicity
• Hives (urticaria)
• Hyperkalaemia (high levels of potassium in the bloodstream)
• Hyperpnoea (breathing that becomes exaggerated, deep or laboured)
• Hyperuricaemia (excess of uric acid in the blood)
• Hyperventilation
• Hypoglycaemia (low blood sugar levels) and hyperglycaemia (elevated blood sugar levels)
• Hypotension (low blood pressure)
• Hypothermia (a medical emergency wherein the body loses heat faster than it produces it) and hyperthermia (a condition wherein the body overheats to dangerous levels)
• Increased thirst
• Interstitial nephritis (inflammation of the tissues in between renal tubules)
• Lethargy, weakness and feeling sluggish
• Light-coloured stools
• Liver failure (hepatic insufficiency)
• Loss of appetite
• Metabolic acidosis (accumulation of acid in the body)
• Muscular cramping, weakness or tremors
• Nosebleeds (epistaxis)
• Numbness or tingling sensations, especially in the hands and feet
• Pain in the lower back or side (flank)
• Pancreatitis
• Proteinuria (abnormal amounts of protein in urine)
• Pulmonary oedema (excess fluid in the lungs)
• Purpura (the formation of blood spots or skin haemorrhages which may be purplish in colour)
• Renal function impairment or failure
• Renal papillary necrosis (death of renal papillae)
• Respiratory alkalosis (a condition that develops to a disruption in the body’s acid-base balance as a result of hyperventilation, it may be caused by a number of conditions including head injury, stroke, pain, pneumonia, asthma, pulmonary embolism and oedema as well as certain medications).
• Rhabdomyolysis (deterioration of skeletal muscle tissue)
• Salt and water retention
• Shortness of breath (dyspnoea)
• Skin rash
• Subdural or intracranial haemorrhage in the brain (bleeding in the brain)
• Tachycardia (a heart rate that exceeds the normal resting rate)
• Tachypnoea (rapid breathing)
• Tinnitus (‘ringing in the ears’)
• Unexplained weight gain
• Vomiting of blood (haematemesis)
• Yellowing of the skin and eyes (jaundice)

Some potential signs of overdose can include:

• Abnormally excitable (overly excited)
• Becoming talkative and incoherent (i.e. speaking in a manner that does not make much sense)
• Breathing problems
• Burning sensation (pain) in the stomach or throat
• Confusion
• Decreased urination output (passing a reduced amount of urine)
• Dizziness
• Double vision
• Drowsiness
• Fearful feelings
• Fever
• Hallucinations
• Insomnia or sleep disturbances
• Irritability
• Loss of consciousness
• Restlessness or nervousness
• Reye’s syndrome
• Seizures or convulsions
• Uncontrollable shaking (involuntary)
• Vomiting and severe nausea 

Should any of the aforementioned symptoms develop, an overdose of aspirin may have occurred. In this instance a person will require immediate medical assistance and must be transported to an emergency medical facility for prompt treatment.

Allergic reactions to aspirin, such as breathing difficulties, the development of hives, blistered or peeling skin, wheezing, tightness of the chest or throat and swelling affecting the facial area, lips, tongue and throat, should also receive swift medical attention. Persistent fever, swelling or pain should also be attended to by a medical doctor as soon as possible.