Thromboass 75 mg

What Is Thromboass and What Is It Used For?

Thromboass contains the active substance acetylsalicylic acid — commonly known as aspirin — at a dose of 75 mg per tablet. At this low dose, the therapeutic goal is not analgesia or anti-inflammation but rather an antiplatelet effect that reduces the likelihood of arterial clot formation. The medication belongs to the pharmacological class of platelet aggregation inhibitors (ATC code B01AC06), a subgroup of the non-steroidal anti-inflammatory drug (NSAID) family, used specifically in cardiovascular medicine.

Thromboass tablets are gastro-resistant (enteric-coated). The coating is designed to resist the acidic environment of the stomach and dissolve only when the tablet reaches the more alkaline environment of the small intestine. Historically, this formulation was developed with the aim of reducing direct gastric irritation. Current high-quality evidence — including the ADAPTABLE trial — indicates that enteric coating does not meaningfully reduce serious gastrointestinal bleeding, because most aspirin-induced bowel injury is mediated by systemic inhibition of protective prostaglandins rather than local contact with the stomach wall. Nevertheless, the enteric coating remains a widely used and well-tolerated formulation.

The clinical effect of Thromboass is based on the irreversible inhibition of cyclooxygenase-1 (COX-1), the enzyme that platelets use to produce thromboxane A2 — a potent promoter of platelet aggregation and vasoconstriction. By permanently acetylating COX-1 in circulating platelets, acetylsalicylic acid blocks thromboxane A2 synthesis for the remainder of each platelet’s 7–10 day lifespan. Because platelets lack a cell nucleus and cannot synthesise new COX-1 enzyme, the antiplatelet effect accumulates with daily dosing until a steady state of inhibited platelet function is reached. This pharmacological property is why once-daily low-dose aspirin is sufficient for sustained cardiovascular protection.

Thromboass 75 mg is indicated for the following conditions, in line with the guidelines of the European Society of Cardiology (ESC), the American Heart Association / American College of Cardiology (AHA/ACC), and NICE:

• Secondary prevention of myocardial infarction (heart attack) — in patients with a previous heart attack or established coronary artery disease.
• Secondary prevention of ischaemic stroke and transient ischaemic attack (TIA) — to reduce the risk of recurrent cerebrovascular events.
• Unstable angina pectoris and acute coronary syndromes — as part of acute and long-term antithrombotic management.
• After coronary artery bypass graft (CABG) surgery — to maintain graft patency and reduce post-operative thrombotic risk.
• After percutaneous coronary intervention (PCI) with stent placement — typically as one component of dual antiplatelet therapy (DAPT) alongside a P2Y12 inhibitor such as clopidogrel, ticagrelor, or prasugrel.
• Peripheral arterial disease (PAD) — to reduce cardiovascular mortality and symptomatic progression in patients with atherosclerotic limb disease.
• Atrial fibrillation — only in selected cases where oral anticoagulants are contraindicated or not tolerated, as modern guidelines prefer anticoagulants over aspirin for stroke prevention in AF.

An important clinical distinction must be drawn between secondary prevention (patients with known cardiovascular disease) and primary prevention (individuals without established disease). Thromboass is primarily indicated for secondary prevention, where the absolute benefits clearly exceed bleeding risks. The role of low-dose aspirin in primary prevention has been substantially narrowed following the ASPREE, ARRIVE, and ASCEND trials, which showed that in most lower-risk adults — including older adults without diabetes or established cardiovascular disease — the bleeding harms outweigh the cardiovascular benefit. The 2019 AHA/ACC Primary Prevention Guideline and 2024 ESC Guidelines consequently limit primary-prevention aspirin to carefully selected higher-risk patients without elevated bleeding risk.

What Should You Know Before Taking Thromboass?

Before initiating Thromboass, your prescribing physician will perform a thorough assessment of your individual benefit–risk balance. While low-dose aspirin offers substantial cardiovascular protection for appropriately selected patients, it is not suitable for everyone, and its bleeding risks must be carefully weighed against the expected therapeutic benefit. Understanding the contraindications, warnings, and precautions is essential for safe long-term use.

Contraindications

You must not take Thromboass if any of the following apply:

• Known hypersensitivity to acetylsalicylic acid, other salicylates, other NSAIDs, or any of the tablet excipients. Allergic reactions can range from mild urticaria to bronchospasm, angioedema, and in rare cases anaphylaxis.
• Aspirin-induced asthma or aspirin-exacerbated respiratory disease (AERD), also known as Samter’s triad (aspirin sensitivity, nasal polyps, and asthma).
• Active peptic ulcer disease, including current gastric or duodenal ulcers, or a history of recurrent peptic ulceration.
• Active gastrointestinal or other clinically significant bleeding (including intracranial haemorrhage).
• Haemophilia or other bleeding disorders, such as von Willebrand disease, thrombocytopenia, or thrombocytopathy.
• Severe hepatic impairment (Child-Pugh class C), due to altered drug metabolism and increased bleeding risk.
• Severe renal impairment (estimated glomerular filtration rate <30 mL/min/1.73 m²), due to accumulation and increased risk of acute kidney injury.
• The third trimester of pregnancy, owing to the risk of premature closure of the fetal ductus arteriosus, prolonged labour, and increased maternal and neonatal bleeding.
• Concomitant use of methotrexate at doses of 15 mg or more per week, because aspirin reduces methotrexate clearance and increases its toxicity.

Warnings and Precautions

Exercise particular caution and discuss the following conditions with your doctor before or during treatment:

• History of gastrointestinal ulceration, bleeding, or perforation — your doctor may co-prescribe a proton pump inhibitor (PPI), such as omeprazole or pantoprazole, for gastric protection.
• Uncontrolled hypertension — particularly when combined with other antiplatelet or anticoagulant agents, this increases the risk of haemorrhagic stroke.
• Gout or hyperuricaemia — low-dose aspirin reduces renal uric acid excretion and can precipitate gout attacks in susceptible individuals.
• Glucose-6-phosphate dehydrogenase (G6PD) deficiency — aspirin can trigger acute haemolytic anaemia in affected patients.
• Asthma, chronic rhinitis, or nasal polyposis — heightened risk of bronchospasm and hypersensitivity reactions.
• Liver or kidney disease (mild to moderate) — requires careful risk assessment and regular monitoring.
• Scheduled surgery or dental procedures — inform the treating clinician, as temporary discontinuation may be necessary. For most patients on aspirin for secondary prevention, continuation through minor procedures is preferred; in major surgery, the decision is individualised based on bleeding and thrombotic risk.
• Heavy alcohol consumption — significantly increases the risk of gastrointestinal bleeding.
• Menorrhagia or planned pregnancy — discuss with your doctor, as aspirin prolongs bleeding.
• Elderly patients — increased baseline risk of bleeding complications, particularly intracranial and upper GI bleeding; periodic reassessment of the benefit–risk profile is recommended.

Pregnancy and Breastfeeding

The use of acetylsalicylic acid during pregnancy requires careful medical assessment. During the first and second trimesters, low-dose aspirin (75–150 mg daily) may be prescribed under specialist supervision — most commonly for the prevention of pre-eclampsia and related placental disorders in women at high risk. This evidence-based use is supported by the WHO, the International Society for the Study of Hypertension in Pregnancy (ISSHP), NICE guideline NG133, and the ASPRE trial, which demonstrated a substantial reduction in preterm pre-eclampsia when aspirin was started before 16 weeks of gestation.

During the third trimester (from approximately week 28 onwards), acetylsalicylic acid is contraindicated. At this stage, it can cause premature closure of the ductus arteriosus in the fetus, inhibit uterine contractions and prolong labour, and increase the risk of maternal and neonatal haemorrhage. Prolonged third-trimester exposure has also been associated with reduced amniotic fluid volume (oligohydramnios) and impaired fetal renal function. If you are taking Thromboass and become pregnant, contact your doctor as soon as possible to review continuation or discontinuation.

Regarding breastfeeding, small amounts of acetylsalicylic acid and its metabolites pass into breast milk. Single, occasional doses are generally considered compatible with breastfeeding. However, regular long-term use during breastfeeding should be avoided where possible, because of a theoretical risk of Reye’s syndrome in the infant and the potential for platelet function effects in the neonate. The British National Formulary (BNF) and LactMed both advise consulting a clinician before regular use. If Thromboass is indicated for the mother’s cardiovascular health, the decision to continue breastfeeding should be made jointly by the mother, obstetrician, cardiologist, and paediatrician.

How Does Thromboass Interact with Other Drugs?

Drug interactions are a major consideration for any patient on long-term low-dose aspirin therapy. Because acetylsalicylic acid alters platelet function and systemic prostaglandin synthesis, it can interact with multiple drug classes — either increasing bleeding risk, reducing the efficacy of other drugs, or changing the effect of aspirin itself. The tables below summarise the most clinically significant interactions.

Major Interactions

Minor Interactions

This list is not exhaustive. Always inform your doctor, pharmacist, or other healthcare professional about every medication you currently take or plan to take — including prescription drugs, over-the-counter medicines, vitamins, and herbal supplements. If in doubt, ask your pharmacist before starting any new product.

What Is the Correct Dosage of Thromboass?

Dosage should always be determined by the prescribing physician based on the indication, underlying disease, bleeding risk, renal function, and concurrent medications. The guidance below reflects typical international clinical practice.

Adults

Children and Adolescents

Thromboass is not recommended for children or adolescents under 16 years because of the risk of Reye’s syndrome. In rare paediatric conditions such as Kawasaki disease, aspirin may be used at specialist-directed doses. Parents and caregivers must never use Thromboass or any aspirin product for fever or pain in children without explicit paediatric advice.

Elderly

Older adults have a higher baseline risk of both gastrointestinal and intracranial bleeding. The standard 75 mg once-daily dose remains appropriate, but the prescribing physician should carefully weigh benefits against bleeding risk, particularly in patients aged 75 years and older. The NICE Clinical Knowledge Summaries recommend that elderly patients on long-term aspirin be reviewed periodically and that co-prescription of a proton pump inhibitor be considered for gastric protection, especially when other gastrotoxic drugs or risk factors are present.

Renal and Hepatic Impairment

In patients with moderate renal impairment (eGFR 30–59 mL/min/1.73 m²) or mild-to-moderate hepatic impairment, dose adjustment is generally not required, but close clinical monitoring is advised. In severe impairment of either kidney or liver function, Thromboass is contraindicated.

Missed Dose

If you forget to take a dose, take it as soon as you remember on the same day. If it is almost time for your next scheduled dose, skip the missed dose and resume your normal routine. Never double the dose to make up for a missed tablet. Because aspirin’s antiplatelet effect persists for the full 7–10 day lifespan of each platelet, a single missed dose is very unlikely to cause a clinical problem — but long-term adherence matters for sustained protection.

Overdose

Aspirin overdose (salicylate poisoning) is a medical emergency. Mild toxicity may present with tinnitus (ringing in the ears), hearing changes, headache, dizziness, nausea, vomiting, and hyperventilation. Severe overdose can cause metabolic acidosis, respiratory alkalosis, hyperthermia, confusion, seizures, coma, and cardiovascular collapse. If an overdose is suspected, contact emergency services or your local poison control centre immediately. Treatment is supportive and may include activated charcoal (if within an hour of ingestion), intravenous fluids, sodium bicarbonate to alkalinise the urine and enhance salicylate excretion, and in severe cases haemodialysis.

What Are the Side Effects of Thromboass?

Like all medicines, Thromboass can cause side effects, although not everybody experiences them. At 75 mg daily, the overall side-effect burden is lower than with higher analgesic or anti-inflammatory doses of aspirin. However, because Thromboass is typically taken long-term — often for years or even lifelong — even infrequent adverse effects become clinically relevant at a population level. The categories below follow standard MedDRA frequency conventions.

Stop taking Thromboass and seek urgent medical attention if you experience any of the following: black or bloody stools; vomiting blood or material that resembles coffee grounds; severe or persistent abdominal pain; signs of an allergic reaction (swelling of face, lips, tongue, or throat; difficulty breathing; severe skin rash; dizziness); unexplained bruising or prolonged bleeding; or sudden, severe headache, weakness on one side of the body, confusion, or changes in vision (which may indicate intracranial bleeding).

The risk of gastrointestinal adverse effects can be reduced by taking Thromboass with or after food, using the lowest effective dose, avoiding concurrent NSAIDs, limiting alcohol, and considering co-prescription of a proton pump inhibitor in higher-risk patients. Patients at elevated GI bleeding risk include those aged over 65, those with a history of peptic ulceration, and those receiving concurrent anticoagulants, corticosteroids, or SSRIs.

How Should You Store Thromboass?

Correct storage is essential to maintain the efficacy and safety of Thromboass throughout its shelf life. Acetylsalicylic acid is susceptible to degradation by heat and moisture, which can hydrolyse the active ingredient into salicylic acid and acetic acid — recognisable by a sharp, vinegar-like odour. The enteric coating is also sensitive to moisture, which can compromise its gastro-resistant properties.

• Temperature: Store below 25 °C (77 °F). Do not freeze. Avoid locations with temperature extremes, such as near radiators, on sunny windowsills, in vehicles, or in humid bathrooms.
• Moisture protection: Keep tablets in the original blister packaging until the moment of use. Moisture accelerates aspirin hydrolysis and can damage the enteric coating.
• Light protection: Store in the original outer carton to protect from direct light.
• Child safety: Keep this medicine out of the sight and reach of children. Accidental aspirin overdose is a well-recognised paediatric emergency, and fatalities have occurred at relatively low ingested doses.
• Expiry date: Do not use Thromboass after the expiry date printed on the packaging. The date refers to the last day of that month.

Do not dispose of medicines in household waste or via the drainage system. Return any unused or expired tablets to your local pharmacy for disposal in line with national environmental regulations. Correct disposal protects waterways and prevents accidental ingestion by children, pets, or other household members.

If tablets have developed an unusual smell (particularly a vinegar-like odour), have changed colour, or show visible coating damage, do not use them — these are signs that the acetylsalicylic acid may have degraded and may no longer be safe or effective.

What Does Thromboass Contain?

Understanding the full composition of your medicine is important if you have allergies, intolerances, or other dietary sensitivities. Each Thromboass 75 mg gastro-resistant tablet contains the following components:

Active Ingredient

• Acetylsalicylic acid — 75 mg per tablet. This is the pharmacologically active substance responsible for the antiplatelet effect.

Excipients (Inactive Ingredients)

Excipients provide the tablet’s structural integrity, stability, and controlled release characteristics. Typical excipients used in enteric-coated low-dose aspirin formulations include:

• Microcrystalline cellulose — a filler and binder that supports tablet structure.
• Maize (corn) starch — a disintegrant that helps the tablet break down after the coating has dissolved.
• Colloidal anhydrous silica — a flow agent that ensures uniformity during manufacturing.
• Stearic acid or magnesium stearate — a lubricant preventing tablets from sticking to production equipment.
• Powdered cellulose or lactose (in some formulations) — diluents used to achieve the correct tablet weight.
• Enteric coating polymers — typically methacrylic acid copolymers (for example, Eudragit L or similar), triethyl citrate as a plasticiser, talc, and titanium dioxide. These polymers resist gastric acid and dissolve in the small intestine.

The enteric (gastro-resistant) coating is one of the defining characteristics of the Thromboass formulation. It delays release of acetylsalicylic acid until the tablet reaches the small intestine, which historically was believed to reduce direct gastric mucosal irritation. Contemporary evidence from large trials, including ADAPTABLE, indicates that the enteric coating does not meaningfully reduce serious gastrointestinal bleeding, because most aspirin-induced GI injury is mediated by systemic (not local) inhibition of protective mucosal prostaglandins. Nevertheless, enteric-coated formulations remain widely used and are generally well tolerated.

If you have lactose intolerance, coeliac disease, corn or maize allergy, or any other dietary sensitivity, always check the current patient information leaflet (PIL) supplied with your specific pack, as the exact excipient composition can vary between manufacturers, markets, and batches. If in doubt, consult your pharmacist.