Acetylsalicylic acid (Aspirin) MEDECIN ABONNE

Indications:

– Symptomatic treatment of mild to moderate pain and/or febrile states.
– Chronic inflammatory rheumatism, acute articular rheumatism in children.
– Symptomatic treatment of inflammatory rheumatism in adults.

Dosage:

Mild to moderate pain and/or feverish states: Reserved for adults and children from 30 kg (approximately 9 to 15 years).

  • Adult and child weighing more than 50 kg (from about 15 years):
    The maximum recommended daily dose is 3 g of aspirin.
    The usual dosage is 500 mg, to be renewed if necessary after 4 hours minimum.
    In case of more intense pain or fever: 1000 mg, to be renewed if necessary after 4 hours minimum, without exceeding 3 grams per day.
  • Elderly:
    The maximum recommended daily dose is 2 g of aspirin.
    The usual dosage is 500 mg, to be renewed if necessary after 4 hours minimum.
    In case of more intense pain or fever: 1000 mg, to be renewed if necessary after 4 hours minimum, without exceeding 2 grams per day.
  • Child 30-50 kg (approximately 9-15 years):

In children, it is imperative to respect the dosages defined according to the weight of the child and therefore to choose an appropriate presentation. Approximate ages by weight are given for information.
The recommended daily dose of acetylsalicylic acid is approximately 60 mg/kg/day, divided into 4 or 6 doses, i.e. approximately 15 mg/kg every 6 hours or 10 mg/kg every 4 hours.

    • Child weighing 30 to 40 kg (approximately 9 to 13 years): the dosage is 500 mg per dose, to be renewed if necessary after 6 hours, without exceeding 2 grams per day.
    • Child weighing 41 to 50 kg (approximately 12 to 15 years): the dosage is 500 mg per dose, to be renewed if necessary after 4 hours, without exceeding 3 grams per day.
  • Frequency of administration: Systematic intakes avoid oscillations of pain or fever:
    – in adults: catches must be spaced at least 4 hours apart;
    – in children (from 30 to 50 kg, i.e. approximately from 9 years to 15 years): catches must be regularly spaced, including at night: comply with the dosage specified above.Duration of treatment: The patient should be informed not to use acetylsalicylic acid for more than 3 days in case of fever and 5 days in case of pain without the advice of a doctor or dentist.

Rheumatic conditions:

Reserved for adults and children from 20 kg.

  • Adult : 3 to 6 g maximum per day to be divided into 3 or 4 doses spaced at least 4 hours apart.
  • Elderly: the dosage will be reduced.
  • Child (this presentation is reserved for children from 20 kg): 50 mg/kg to 100 mg/kg maximum per day, to be divided into 4 to 6 doses spaced at least 4 hours apart.

Mode of administration: Oral route.

Contraindications:

– Hypersensitivity to acetylsalicylic acid or to any of the excipients.
– Phenylketonuria, if aspartame is present in the gallenic form.
– History of asthma caused by the administration of salicylates or substances with similar activity, in particular non-steroidal anti-inflammatory drugs.
– Last trimester of pregnancy (≥ 500 mg per day and per intake): see Fertility/Pregnancy/Breastfeeding.
– Evolving peptic ulcer.
– Any constitutional or acquired haemorrhagic disease.
– Hemorrhagic risk.
– Severe liver failure.
– Severe kidney failure.
– Severe uncontrolled heart failure.
– Combination with methotrexate at doses greater than 15 mg/week (see Interactions).
– Combination with oral anticoagulants when aspirin is used in high doses (see Interactions), especially in the treatment of rheumatic conditions.

Warnings and precautions for use:

– In the event of association with other medicinal products, to avoid a risk of overdose, check the absence of acetylsalicylic acid in the composition of the other medicinal products.
– In case of long-term administration of analgesic drugs in high doses, the occurrence of headaches (headaches) should not be treated with higher doses.
– The regular use of analgesics, in particular the combination of analgesics, can lead to persistent kidney damage with a risk of renal failure.
Reye’s syndromes, very rare but life-threatening pathologies, have been observed in children with signs of viral infections (particularly chicken pox and flu-like episodes) and receiving acetylsalicylic acid. Consequently, acetylsalicylic acid should only be administered to these children on medical advice, when other measures have failed.
If persistent vomiting, impaired consciousness or abnormal behavior occurs, treatment with acetylsalicylic acid should be discontinued.
– In some cases of severe form of G6PD deficiency, high doses of acetylsalicylic acid may have caused haemolysis. The administration of acetylsalicylic acid in case of G6PD deficiency must be done under medical supervision.
– In children under 1 month, the administration of acetylsalicylic acid is only justified in certain situations subject to medical prescription.
– Treatment monitoring should be reinforced in the following cases:

  • history of peptic ulcer, gastrointestinal bleeding or gastritis;
  • kidney or liver failure;
  • asthma: the occurrence of an asthma attack, in some subjects, may be linked to an allergy to nonsteroidal anti-inflammatory drugs or acetylsalicylic acid. In this case, this drug is contraindicated;
  • metrorrhagia or menorrhagia (risk of increased importance and duration of menstruation);
  • use of an IUD- Gastrointestinal bleeding or ulcers/perforations may occur at any time during treatment without necessarily having any prior symptoms or history. The relative risk increases in the elderly, the subject of low body weight, the patient undergoing anticoagulant or antiplatelet treatment (see Interactions).
    In the event of gastrointestinal bleeding, discontinue treatment immediately.
    – Given the antiplatelet effect of acetylsalicylic acid, which appears from very low doses and persists for several days, the patient should be warned of the risk of bleeding that may occur in the event of even minor surgery (e.g. dental extraction) .
    – Acetylsalicylic acid modifies uricemia (at analgesic doses, acetylsalicylic acid increases uricemia by inhibiting the excretion of uric acid; at doses used in rheumatology, acetylsalicylic acid has a uricosuric effect).
    – Particularly rigorous medical supervision is essential for the following drug combinations (see Interactions):

    • oral anticoagulants and low-dose aspirin;
    • other nonsteroidal anti-inflammatory drugs and high-dose aspirin (>3g/d);
    • antiplatelet agents, parenteral heparins, uricosurics (benzbromarone, probenecid), antidiabetics (insulins), diuretics and high-dose aspirin (> 3g/d), systemic glucocorticoids (except hydrocortisone used as replacement therapy in Addison’s disease), ACE inhibitors and, by extrapolation, angiotensin II antagonists (for high dose aspirin, > 3 g/d), methotrexate (at doses < 15 mg/week).

– At the high doses used in rheumatology, it is recommended to monitor the appearance of signs of overdose. If ringing in the ears, decreased hearing acuity and vertigo appear, the treatment modalities should be reassessed.

– In children, it is recommended to monitor salicylemia, especially when starting treatment.

Interaction:

Drugs interactions :

Several substances are involved in the interactions, due to their antiplatelet properties: aspirin and NSAIDs, ticlopidine and clopidogrel, tirofiban, eptifibatide and abciximab, iloprost.
The use of several antiplatelet agents increases the risk of bleeding, as well as their association with heparin or analogues (hirudins), oral anticoagulants and thrombolytics, and must be taken into account by maintaining regular clinical and biological monitoring. .

Contraindicated :

Oral anticoagulants (for aspirin at high doses > 3 g/day): displacement of the oral anticoagulant from its plasma protein bonds.
Methotrexate used at doses > 15 mg/week: increased toxicity, in particular haematological, of methotrexate (decreased renal clearance of methotrexate by anti-inflammatories in general and displacement of methotrexate from its binding to plasma proteins by aspirin).

Not recommended:

Oral anticoagulants (for low-dose aspirin): increased risk of bleeding (inhibition of platelet function and aggression of the gastroduodenal mucosa). Need for control, especially bleeding time.
Other non-steroidal anti-inflammatory drugs (for aspirin at high doses > 3 g/day): increased risk of ulcerogenic and digestive bleeding (additive synergy).
Heparins (parenteral route): increased risk of bleeding (inhibition of platelet function and aggression of the gastroduodenal mucosa by aspirin). Use substances other than aspirin for an analgesic and antipyretic effect (particularly paracetamol).
Uricosurics (benzbromarone, probenecid); for benzbromarone: described for doses of aspirin ≤ 3 g/d: decrease in the uricosuric effect by competing with the elimination of uric acid in the renal tubules. Use another pain reliever.

Requiring precautions for use:

Antidiabetics (insulins): increased hypoglycemic effect with high doses of acetylsalicylic acid (hypoglycemic action of acetylsalicylic acid). Warn the patient and strengthen glycemic self-monitoring.
Diuretics (for high-dose aspirin > 3 g/day): acute renal failure in dehydrated patients (reduction in glomerular filtration by reduction in the synthesis of renal prostaglandins). Moreover, reduction of the antihypertensive effect. Hydrate the patient; Look at the kidney function at the start of the treatment.
Corticosteroids (gluco-, systemic), except hydrocortisone used as replacement therapy in Addison’s disease: decrease in salicylemia during treatment with corticosteroids and risk of overdose of aspirin after its discontinuation (increased elimination aspirin with corticosteroids). Adaptation of aspirin doses during the combination and after stopping treatment with glucocorticoids.
ACE inhibitors and angiotensin II antagonists by extrapolation (for aspirin at high doses > 3 g/d): acute renal failure in patients at risk (elderly and/or dehydrated subject) by reduction glomerular filtration by inhibition of vasodilating prostaglandins due to salicylates. Hydrate the patient; Look at the kidney function at the start of the treatment.
Methotrexate used at doses < 15 mg/week: increased toxicity, in particular haematological, of methotrexate (decreased renal clearance of methotrexate by anti-inflammatories in general and displacement of methotrexate from its binding to plasma proteins by aspirin). Weekly control of the blood count during the first weeks of the association. Increased monitoring in the event of impairment (even slight) of renal function, as well as in the elderly.

To consider :

Intrauterine device (for aspirin at high doses > 3 g/d): risk (controversial) of reduced effectiveness of intrauterine devices.
Gastrointestinal topical (salts, oxides and hydroxides of magnesium, aluminum and calcium): increased renal excretion of aspirin by alkalinization of urine.

Pregnancy and breast feeding :

Pregnancy :

First and second trimester of pregnancy:
– Acetylsalicylic acid can be prescribed as a one-off treatment if needed;
– as a precautionary measure, it is preferable not to use acetylsalicylic acid in chronic treatment beyond 150 mg/d.

Third trimester of pregnancy:
Acetylsalicylic acid at doses ≥500mg per dose per day, like all prostaglandin synthesis inhibitors, may expose:
– the fetus has cardiopulmonary toxicity (with premature closure of the arterial duct and pulmonary hypertension) and renal dysfunction that can go as far as renal failure with oligohydramnios;
– the mother and the child, at the end of pregnancy, to a lengthening of the bleeding time. This antiaggregating effect can occur even at very low doses. Consequently: Apart from extremely limited cardiological or obstetrical uses, which warrant medical advice and specialized monitoring, any drug containing acetylsalicylic acid is contraindicated during the last trimester of pregnancy.

Feeding with milk :


As acetylsalicylic acid passes into breast milk, this medication is not recommended during breastfeeding.

Side effects :

Gastrointestinal effects:

  • abdominal pain ;
  • patent digestive bleeding (haematemesis, melæna…) or occult, responsible for iron deficiency anemia. These haemorrhages are all the more frequent as the dosage is higher; gastric ulcers and perforations.

Central Nervous System Effects:

Usually the hallmark of an overdose:
– headache, dizziness;
– feeling of decreased hearing acuity;
– ringing in the ears;

Hematological effects:

– haemorrhagic syndromes (epistaxis, gingival bleeding, purpura, etc.) with increased bleeding time. This action persists 4 to 8 days after stopping acetylsalicylic acid. It can create a haemorrhagic risk in the event of surgical intervention.

Hypersensitivity reaction:

Urticaria, skin reactions, anaphylactic reactions, asthma, angioedema.

Reye’s syndrome

Overdose:

Poisoning is to be feared in the elderly and especially in young children (therapeutic overdose or frequent accidental poisoning) where it can be fatal.

Symptoms :

Moderate poisoning:

ringing in the ears, sensation of decreased hearing acuity, headache, dizziness, are the mark of an overdose and can be controlled by reducing the dosage.

Severe poisoning:

in children, overdose can be fatal from 100 mg/kg in a single dose. Symptoms are: fever, hyperventilation, ketosis, respiratory alkalosis, metabolic acidosis, coma, cardiovascular collapse, respiratory failure, significant hypoglycemia.

Emergency driving:

– Immediate transfer to a specialized hospital.
– Digestive decontamination and administration of activated charcoal.
– Control of the acid base balance.
– Alkaline diuresis to obtain a urinary pH between 7.5 and 8, possibility of hemodialysis in serious poisoning.
– Symptomatic treatment.

 

Post operative chronic pain