Aspirin 300mg tablets contain acetylsalicylic acid for the relief of mild to moderate pain, including headache, migraine, toothache, period pain, rheumatic pain, and cold and flu symptoms in adults and young people aged 16 and over.
Available as a general sale medicine (GSL) from any retailer without a prescription, they are also used as first aid in suspected myocardial infarction.
Each pack contains 32 tablets. Courier Pharmacy provides expert guidance to help you use aspirin safely.
Aspirin 300mg tablets contain acetylsalicylic acid, a salicylate compound and non-selective non-steroidal anti-inflammatory drug (NSAID) with four distinct pharmacological properties: analgesia, antipyresis, anti-inflammation, and irreversible platelet inhibition. Each tablet contains 300mg of aspirin, the standard analgesic dose for adults. The 32-tablet pack is a general sale medicine (GSL). This means that aspirin 300mg tablets are available from any retailer without a prescription or pharmacist consultation.
How aspirin works
Aspirin’s pharmacological profile is broader than most single-ingredient OTC medicines. Its analgesic and anti-inflammatory effects are shared with other NSAIDs such as ibuprofen. However, its irreversible inhibition of platelet COX-1 is unique.
Where ibuprofen’s antiplatelet effect is reversible and resolves within hours of clearance, aspirin’s acetylation of the COX-1 enzyme is permanent for the lifespan of the platelet.
This antiplatelet property has made 75mg aspirin a cornerstone of secondary cardiovascular prevention, though this low-dose use is clinically separate from the 300mg analgesic dose covered here.
The history of aspirin
The history of aspirin is genuinely remarkable. Acetylsalicylic acid was first synthesised in its stable form by Bayer in 1897, building on earlier use of willow bark extracts containing salicin. It has since become one of the most studied, most prescribed, and most recognised medicines on earth.
That longevity reflects a genuine clinical track record across an extraordinary range of applications. Understanding aspirin properly, including its contraindications and interactions, is something every adult who uses it deserves.
Key features and specifications
Active ingredient: acetylsalicylic acid 300mg per tablet
Drug class: non-selective NSAID and antiplatelet agent
Pack size: 32 tablets
Legal category: general sale medicine (GSL)
Suitable for: adults and young people aged 16 and over
Licensed indications: headache, migraine, toothache, period pain, neuralgia, sore throat, rheumatic and muscular pain, cold and flu symptoms, first aid for suspected MI
Usual analgesic dose: one to two tablets every four to six hours, maximum eight tablets in 24 hours
Additional information
Quantity
1 x 28, 2 x 28, 3 x 28
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Being one of the oldest and most studied medicines in the world — aspirin 300mg is worth knowing properly
Aspirin has been in clinical use for over a century, which puts it in a fairly exclusive club. Few medicines have been studied as extensively, used as widely, or understood as thoroughly as acetylsalicylic acid. Aspirin 300mg tablets are a general sale medicine used for the relief of mild to moderate pain, including headache, period pain, toothache, sore throat, rheumatic pain, and the aches and fever associated with colds and flu.
They are also the first port of call in a suspected heart attack. At Courier Pharmacy, we believe healthcare should fit the person, and that means giving you clear, complete information about a medicine you can already buy from a supermarket, not just a label summary. Whether you are reaching for aspirin as an everyday analgesic, want to understand it in the context of a broader health picture, or simply want to know what you are actually swallowing, this is the place to start.
Five things worth knowing straight away
Aspirin 300mg tablets contain acetylsalicylic acid, a non-selective NSAID with analgesic, antipyretic, anti-inflammatory, and irreversible antiplatelet properties.
They are a general sale medicine (GSL), available without a prescription or pharmacist supervision from any retailer.
Aspirin must not be given to children or young people under 16 due to the risk of Reye’s syndrome, a rare but serious condition affecting the liver and brain.
A single dose of 300mg aspirin at the first sign of a suspected heart attack can be life-saving; chew one tablet and call 999 immediately.
Aspirin’s antiplatelet effect is irreversible and persists for the entire lifespan of the platelet (seven to ten days); this is clinically significant for surgery, dental procedures, and anyone on anticoagulant therapy.
Treatment dosage: aspirin 300mg tablets
Always follow the dosage instructions on the pack. The guidance below is based on standard BNF dosing and SmPC information for aspirin 300mg at analgesic doses and should not replace personalised advice from a healthcare professional.
For adults and young people aged 16 and over for pain or fever: take one to two tablets every four to six hours as needed. Do not exceed eight tablets in any 24-hour period. Take with or after food and with a full glass of water. Space doses at least four hours apart.
For suspected myocardial infarction: chew one tablet (300mg) immediately and call 999. Chewing accelerates buccal absorption, and the antiplatelet effect reaches peak more rapidly than swallowing whole. Do not delay calling 999 to find aspirin; the call comes first.
Do not give to children or young people under 16. Do not use for more than three consecutive days for pain or two days for fever without medical advice. Check all OTC medicines for aspirin content before combining to avoid double-dosing.
Overview of aspirin 300mg tablets
Aspirin belongs to a category of medicines that have become so familiar that people stop thinking about them carefully. That familiarity is not the same as safety. At 300mg, aspirin is a full-dose NSAID with all the gastrointestinal, antiplatelet, and drug interaction implications that come with that class. Its long track record is real, but so are its risks, particularly in people who are elderly, those on anticoagulants, those with peptic ulcer history, and those who combine it with other NSAIDs or alcohol.
The emergency MI use of aspirin is one of the most well-established pieces of first-aid medicine. Aspirin’s irreversible inhibition of platelet COX-1 prevents the thromboxane A2-mediated platelet aggregation that drives arterial thrombosis. In a coronary artery already narrowed by atherosclerosis, a ruptured plaque triggers a platelet cascade that can completely occlude the vessel. A chewed 300mg aspirin rapidly inhibits this cascade and reduces the probability of complete vessel occlusion. This is why ambulance services and emergency departments administer aspirin as an immediate priority to people presenting with suspected acute MI.
The difference between chewing and swallowing aspirin in the context of a suspected heart attack is clinically meaningful. Chewing the tablet promotes buccal absorption and bypasses gastric dissolution, achieving peak plasma levels approximately 15 to 20 minutes faster than with whole-tablet swallowing. In the context of an evolving MI, faster platelet inhibition translates directly into reduced thrombus extension. Current guidance specifies chewing for this reason.
The gastrointestinal risk of analgesic-dose aspirin is real and proportionate to dose and duration. At 300mg to 600mg for short-course acute pain in a healthy adult, the absolute GI risk is low but not zero. Aspirin inhibits gastric COX-1, reducing the prostaglandins that maintain the stomach’s protective mucus and bicarbonate layer. Taking aspirin with food and a full glass of water genuinely reduces this risk by providing a physical buffer and stimulating protective mucus secretion.
People managing general chronic illness sometimes ask whether aspirin is appropriate for their pain alongside their other treatments. The honest answer depends specifically on what else they are taking. Aspirin enhances the antiplatelet and GI effects of other NSAIDs or anticoagulants. For people on anticoagulation therapy, analgesic-dose aspirin significantly increases bleeding risk and is generally contraindicated. For people with a history of peptic ulcer disease, aspirin is also best avoided. Our pharmacists at Courier Pharmacy can help you work through whether aspirin is the right choice for your specific situation.
Why choose Courier Pharmacy for aspirin 300mg tablets
At Courier Pharmacy, we believe healthcare should fit the person. Even for a general sale medicine like aspirin 300mg tablets, that means giving you the honest, complete information you deserve rather than the bare minimum required by a shelf label. Our service is shaped by the philosophy of Dr Ada Jex-Cori, our brand pharmacist, who built her practice on the belief that everyone deserves expert, accessible care. Her message, that you are not broken and the system is the problem we are here to fix, guides how we think about every product we stock and every piece of content we write.
For people managing general chronic illness alongside everyday pain management, aspirin’s interaction profile is genuinely relevant. If you are on anticoagulants, managing a condition that affects platelet function, or taking medicines that interact with salicylates, knowing whether aspirin is the right analgesic is exactly the kind of pharmacist conversation we are here to have. Paracetamol is often safer for people with complex medication regimens, and our pharmacists can help you work out which choice suits your situation best.
Trust is what we earn through transparency, regulation, and consistency. Courier Pharmacy is GPhC-regulated, sources content from NHS, NICE, BNF, and peer-reviewed evidence, and will tell you clearly when aspirin is not the right choice for you and what is.
Buy aspirin 300mg tablets online from Courier Pharmacy
Aspirin 300mg tablets are a general sale medicine (GSL). No prescription or pharmacist consultation is required. You can purchase them directly from our online store.
Here is how our service works:
Browse and select aspirin 300mg tablets from our online store.
Add to your order alongside any other products you need.
We prepare your order and confirm dispatch.
We deliver discreetly to your door.
If you have any questions about whether aspirin is suitable for your situation, our pharmacists are available to advise. We would rather help you make the right choice than simply complete a transaction.
Our free fortnightly drop-in clinics at Insomnia, Derby, run every other fortnight from 10 am to 12 pm. Analgesic safety, NSAID interactions, and understanding which OTC pain relief is right for your medical history are all regular topics. No appointment, no charge, no pressure.
Summary
Aspirin irreversibly acetylates the COX-1 enzyme in platelets, permanently impairing their ability to produce thromboxane A2; because platelets cannot synthesise new protein, this effect lasts the full platelet lifespan of approximately seven to ten days after a single dose.
The anti-inflammatory effect of 300mg aspirin is modest compared with the 3 to 6g daily doses used historically for full anti-inflammatory therapy; at analgesic doses, the primary benefits are analgesia and antipyresis with partial anti-inflammatory effect.
Reye’s syndrome, the reason for the absolute under-16 contraindication, is a rare but potentially fatal condition of acute hepatic failure and encephalopathy triggered by aspirin use during or following a viral illness in children and young people.
Aspirin is absorbed rapidly from the stomach and small intestine, with peak plasma concentrations typically reached within 20 to 40 minutes; this rapid absorption makes chewing clinically meaningful for the emergency MI indication.
Low-dose aspirin (75mg) for cardiovascular prevention and analgesic-dose aspirin (300mg) are pharmacologically distinct clinical applications; taking 300mg on top of daily 75mg does not improve antiplatelet protection and does increase bleeding risk.
Active ingredient in aspirin 300mg tablets
The active ingredient is acetylsalicylic acid (ASA) at 300mg per tablet. Aspirin is a salicylate NSAID that works by irreversibly acetylating the cyclo-oxygenase enzyme at its active site, permanently inactivating it. This differs from all other NSAIDs, which bind reversibly. The irreversibility of aspirin's enzyme inhibition is the mechanistic basis for its unique antiplatelet properties: platelets, which lack nuclei and cannot synthesise new protein, are permanently unable to produce thromboxane A2 once their COX-1 has been acetylated by aspirin, and this impairment lasts the lifespan of the platelet.
Aspirin is rapidly absorbed from the gastrointestinal tract. Peak plasma concentrations are typically reached within 20 to 40 minutes of an oral dose. It is hydrolysed in the gut wall and liver to salicylate, the primary active species for anti-inflammatory and analgesic effects. At the standard 300mg analgesic dose, salicylate plasma half-life is approximately two to three hours, which is why re-dosing every four to six hours is appropriate for sustained analgesia.
What are aspirin 300mg tablets used for?
Aspirin 300mg tablets are licensed for the relief of mild to moderate pain and fever in adults and young people aged 16 and over. Licensed indications include headache, migraine, toothache, period pain, neuralgia, sore throat, rheumatic and muscular pain, cold and flu symptoms, and first aid in suspected myocardial infarction.
For analgesic use, aspirin is appropriate when pain is mild to moderate, and there is no specific contraindication. It is particularly suited to presentations where both analgesic and mild anti-inflammatory effects are desired, such as headache with muscular tension, sore throat with an inflammatory component, or rheumatic and muscular aches. For period pain where prostaglandin excess drives uterine cramping, aspirin's COX inhibition addresses the mechanism directly, which is why NSAIDs are generally more effective than paracetamol for dysmenorrhoea.
Aspirin should not be chosen as a first-line analgesic for people on anticoagulants, those with a history of peptic ulcer or gastric bleeding, those who are pregnant, or those with aspirin-sensitive asthma. For these groups, paracetamol is a safer default. Aspirin is also not appropriate for people who already take 75mg aspirin daily for cardiovascular prevention, as the 300mg dose adds GI risk without meaningful additional analgesic benefit over paracetamol.
How do aspirin 300mg tablets work?
Aspirin's primary analgesic and anti-inflammatory mechanism is the irreversible acetylation and inactivation of cyclo-oxygenase enzymes. These enzymes convert arachidonic acid into prostaglandin H2, which is then converted to various prostaglandins, prostacyclin, and thromboxane A2. These prostanoids are key mediators of the inflammatory cascade: they sensitise peripheral nociceptors, promote vasodilation and increased vascular permeability, and act on the hypothalamus to raise the temperature set-point, causing fever. By irreversibly inhibiting COX enzymes, aspirin reduces prostaglandin synthesis at the site of injury and in the hypothalamus, addressing both the pain signal and the fever simultaneously.
The antipyretic effect is mediated through central prostaglandin inhibition in the hypothalamus. During infection, cytokines such as interleukin-1 and tumour necrosis factor stimulate hypothalamic production of PGE2, which resets the thermoregulatory set-point upward. Aspirin reduces hypothalamic PGE2 synthesis, allowing the temperature set-point to return towards normal. This is why aspirin and paracetamol produce comparable antipyretic effects despite different mechanisms: both ultimately reduce central prostaglandin synthesis.
The antiplatelet mechanism operates specifically via irreversible acetylation of COX-1 in platelets. Thromboxane A2 is a potent promoter of platelet aggregation and vasoconstriction, produced via COX-1. By permanently inactivating platelet COX-1, aspirin prevents TXA2 production for the lifetime of the platelet. Because platelets are enucleate cells unable to synthesise new enzymes, this inhibition is irreversible. As new platelets are generated (approximately 10 per cent of the total platelet pool each day), antiplatelet function gradually recovers over seven to ten days.
The concentration of aspirin required for antiplatelet inhibition is substantially lower than that required for analgesia. A single 75mg tablet is sufficient to maximally inhibit platelet TXA2 production for the life of those platelets. The 300mg analgesic dose provides the same antiplatelet effect plus the additional peripheral COX inhibition needed for pain relief and fever reduction. This is why low-dose and analgesic aspirin are not additive in terms of antiplatelet benefit; the antiplatelet effect is already maximal at 75mg.
How to use aspirin 300mg tablets
Take one to two tablets with a full glass of water, with or after food. The food recommendation is genuinely clinically important: direct contact between aspirin and the gastric mucosa causes local irritation. Food provides a physical buffer and stimulates gastric bicarbonate and mucus secretion, both of which reduce direct mucosal injury. Space doses at least four hours apart and stay within the eight-tablet daily maximum.
Swallow tablets whole for analgesic use. The exception is suspected myocardial infarction, in which chewing results in faster buccal absorption and an earlier onset of antiplatelet effect. For everyday headache or period pain, swallowing whole with food and water is the recommended approach. Do not crush aspirin tablets and dissolve them unless the product is specifically formulated as a dispersible tablet; standard tablets are not designed for this and may not dissolve evenly.
Check all other medicines before taking aspirin. This includes cold and flu remedies, combination headache products, and any prescribed medicines that interact with aspirin or other NSAIDs. Many OTC products contain aspirin, but it's not immediately obvious from the product name. The three-day maximum for pain and two-day maximum for fever are clinical limits, not suggestions; pain that does not improve within these timeframes deserves medical assessment.
Warnings and precautions for aspirin 300mg tablets
Do not give aspirin 300mg to anyone under 16. The aspirin component carries a risk of Reye's syndrome in children and young people during or after viral illnesses. Reye's syndrome is a rare but potentially fatal condition causing acute liver failure and brain swelling, caused by mitochondrial dysfunction in the context of viral infection. This contraindication is absolute regardless of the reason for use; for pain or fever in under-16s, paracetamol or age-appropriate ibuprofen is the correct approach.
Do not take aspirin if you are allergic to aspirin, any other NSAID, or any excipient. NSAID-exacerbated respiratory disease can cause severe bronchospasm following aspirin ingestion. If you have asthma, discuss NSAID use with your pharmacist or GP. Do not take if you have active peptic ulceration, gastric or intestinal bleeding, or a history of recurrent peptic ulcer disease.
Anticoagulants and antiplatelets: Aspirin's irreversible antiplatelet effect, when combined with warfarin, heparin, DOACs, clopidogrel, and other antiplatelet agents, significantly increases bleeding risk. Do not take analgesic-dose aspirin if you are on any anticoagulant or antiplatelet therapy without first discussing it with your prescriber or pharmacist. If you take 75mg aspirin daily for cardiovascular prevention and need an analgesic, paracetamol is generally the safer choice.
Pregnancy: Aspirin is contraindicated in the third trimester and should be avoided in earlier trimesters unless under medical supervision for a specific indication. At 300mg analgesic doses, aspirin is not appropriate during pregnancy. Paracetamol is the recommended first-line OTC option.
Gout: at analgesic doses, aspirin can raise serum uric acid by competing with urate for renal tubular secretion, potentially worsening gout or triggering an acute attack. If you have a history of gout, paracetamol or an NSAID without uricosuric competition is more appropriate.
Side effects of aspirin 300mg tablets
The most commonly reported side effects at analgesic doses relate to the gastrointestinal system. Dyspepsia, nausea, abdominal pain, and heartburn are the most frequent complaints, related to local gastric mucosal exposure and systemic COX-1 inhibition. Taking aspirin with food and a full glass of water substantially reduces the incidence of these mild GI symptoms for most people.
Less common side effects include gastrointestinal bleeding, ranging from occult blood loss to overt haemorrhage presenting as black stools or vomiting blood. At short-course doses in healthy adults without risk factors, overt GI bleeding is uncommon but increases with dose, duration, advancing age, and concurrent anticoagulant or steroid use. Tinnitus is a recognised sign of salicylate accumulation at higher doses; report it to your pharmacist or GP if it occurs during aspirin use.
Rare but serious adverse effects include severe gastrointestinal haemorrhage, anaphylaxis, severe bronchospasm in NSAID-sensitive asthma, and salicylate toxicity in overdose. Signs of salicylate poisoning include tinnitus, dizziness, confusion, rapid breathing, and metabolic acidosis. If you suspect an overdose, seek emergency medical care immediately.
Report suspected adverse drug reactions to the MHRA via the Yellow Card scheme at yellowcard.mhra.gov.uk. Your report contributes to the real-world safety monitoring of medicines, including aspirin.
Drug interactions with aspirin 300mg tablets
Aspirin has a significant interaction profile. Tell your pharmacist about all medicines you are taking before using aspirin regularly or if you are managing a complex medical condition.
Anticoagulants and antiplatelets: aspirin's irreversible antiplatelet effect adds meaningfully to warfarin, heparin, DOACs, clopidogrel, and dipyridamole. Even a single analgesic dose produces platelet inhibition that lasts for days. If you are on any anticoagulant, analgesic-dose aspirin is generally contraindicated without prescriber assessment.
Other NSAIDs, including ibuprofen, naproxen, and diclofenac, add to aspirin's GI adverse effects. Ibuprofen can compete with aspirin for the COX-1 binding site, potentially blocking aspirin's irreversible acetylation and reducing its antiplatelet effect. For people taking low-dose aspirin for cardiovascular protection, concurrent regular ibuprofen use is therefore clinically problematic. Corticosteroids combined with aspirin significantly increase GI bleeding risk.
Methotrexate excretion via the renal tubule can be inhibited by aspirin, raising methotrexate plasma levels and toxicity risk. Uricosuric agents for gout, including probenecid and sulfinpyrazone, have their effects reduced by aspirin through renal tubular competition. SSRIs and SNRIs, when combined with aspirin, increase gastrointestinal bleeding risk through the reduction in serotonin-mediated platelet aggregation; this is a particularly relevant interaction for people on antidepressants who reach for aspirin for a headache.
Oral hypoglycaemics and insulin: aspirin at higher doses has a mild blood glucose-lowering effect and can potentiate the action of sulphonylureas and insulin. This interaction is more relevant with regular high-dose use than with occasional short-course analgesic doses.
Frequently asked questions about aspirin 300mg tablets
What is aspirin 300mg used for?
Aspirin 300mg tablets are used for the relief of mild to moderate pain, including headache, migraine, toothache, period pain, sore throat, rheumatic and muscular pain, and cold and flu symptoms in adults and young people aged 16 and over. They are also used as first aid in suspected myocardial infarction: chew one 300mg tablet and call 999 immediately.
What is the active ingredient in aspirin 300mg tablets?
The active ingredient is acetylsalicylic acid at 300mg per tablet. Acetylsalicylic acid is a salicylate NSAID that irreversibly inhibits cyclo-oxygenase enzymes, reducing prostaglandin synthesis. This produces analgesic, antipyretic, anti-inflammatory, and antiplatelet effects. The irreversible nature of its COX inhibition distinguishes aspirin pharmacologically from all other NSAIDs.
Why can't children under 16 take aspirin?
Aspirin is contraindicated in under-16s due to the risk of Reye's syndrome. When given to a child during or following a viral illness, aspirin can trigger a rare but potentially fatal condition, causing acute liver failure and brain swelling, caused by mitochondrial dysfunction in the context of viral infection. This restriction is absolute. For pain or fever in children and young people, paracetamol or age-appropriate ibuprofen is the preferred analgesic.
Can I take aspirin if I am on blood thinners?
Generally, no, without medical advice. Aspirin's irreversible antiplatelet effect, when combined with warfarin, heparin, DOACs, and other antiplatelet agents, significantly increases bleeding risk. If you are on any anticoagulant therapy, discuss analgesic options with your pharmacist or prescriber before taking aspirin; paracetamol is usually the safer alternative for everyday pain.
How does aspirin help in a heart attack?
In a suspected heart attack, chewing 300mg aspirin immediately inhibits platelet aggregation by permanently inactivating thromboxane A2 production via irreversible COX-1 acetylation. This reduces the platelet cascade driving arterial thrombosis. Chewing rather than swallowing results in faster buccal absorption and earlier antiplatelet effect. Calling 999 is the absolute priority; aspirin supports this while emergency care is on the way.
Can I take aspirin with paracetamol?
In general, yes. Aspirin and paracetamol work through different mechanisms and can generally be taken together for additional pain relief. Aspirin does not contain paracetamol, so the concern is only with other paracetamol-containing products being taken simultaneously. The safe daily paracetamol maximum for adults is 4000mg; check all other products for paracetamol content.
Can I take aspirin with ibuprofen?
Caution is advised. Taking aspirin and ibuprofen together increases GI bleeding risk, and evidence suggests ibuprofen can interfere with aspirin's antiplatelet effect by competing for the COX-1 binding site. This is particularly relevant for people on low-dose aspirin daily for cardiovascular protection. Discuss with your pharmacist if you need to use both.
Can I drink alcohol while taking aspirin?
No. Alcohol increases the risk of gastrointestinal bleeding when combined with aspirin. Even moderate alcohol consumption adds meaningfully to aspirin's gastric mucosal effect and increases the risk of GI haemorrhage. Avoid alcohol during any course of aspirin.
Is aspirin suitable during pregnancy?
Aspirin at 300mg analgesic doses is not recommended during pregnancy. It is contraindicated in the third trimester due to risks including premature closure of the ductus arteriosus. In earlier trimesters, it should be used only under medical supervision for specific indications. Paracetamol is the recommended OTC analgesic during pregnancy.
What is the difference between aspirin 300mg and aspirin 75mg?
Aspirin 300mg is the analgesic dose for pain, fever, and emergency MI first aid. Aspirin 75mg is used for secondary cardiovascular prevention. The antiplatelet effect is already maximal at 75mg; the higher 300mg dose provides the same antiplatelet effect plus analgesic and antipyretic action. Taking 300mg on top of a daily 75mg does not improve cardiovascular protection and does increase GI risk.
Can aspirin cause stomach problems?
Yes. Aspirin inhibits gastric COX-1, reducing protective prostaglandins that maintain the stomach's mucus and bicarbonate layer. This can cause dyspepsia, nausea, and gastric irritation, and with regular or long-term use, increases the risk of peptic ulceration and GI bleeding. Taking aspirin with food and a full glass of water significantly reduces direct gastric mucosal exposure.
How long does aspirin's antiplatelet effect last?
Aspirin's antiplatelet effect lasts the entire lifespan of the platelets it inhibits, approximately 7 to 10 days after a single dose. Because aspirin irreversibly acetylates platelet COX-1 and platelets cannot synthesise new enzyme, the inhibition is permanent until new platelets are generated. This is why surgeons and dentists ask patients to stop taking aspirin 7 to 10 days before procedures with a bleeding risk.
Can aspirin cause tinnitus?
Yes. Tinnitus is a recognised sign of salicylate accumulation, particularly at higher or more frequent doses. At the standard 300mg short-term dose in healthy adults, tinnitus is uncommon. It is more likely in those taking aspirin at maximum dose regularly, in older adults with reduced renal clearance, and in those sensitive to salicylates. Report tinnitus during aspirin use to your pharmacist or GP.
Is aspirin an anti-inflammatory?
Yes, but the anti-inflammatory effect at 300mg analgesic doses is modest compared with the 3 to 6g daily doses historically used for significant inflammatory conditions. At 300-600mg, the primary benefits are analgesia and antipyresis. For significant inflammatory conditions such as rheumatoid arthritis, prescription-strength NSAIDs or disease-modifying treatments are more appropriate.
Can I take aspirin for a migraine?
Yes. Migraine is a licensed indication for aspirin 300mg. Aspirin addresses both vascular and inflammatory components of migraine pain through COX inhibition and cerebral vasoconstriction via salicylate activity. For frequent or severe migraine that do not respond adequately to OTC analgesics, triptans, and other prescription treatments prescribed by a GP are generally more effective.
Does aspirin interact with antidepressants?
SSRIs and SNRIs reduce platelet serotonin levels, impairing serotonin-mediated platelet aggregation. Combined with aspirin, which also inhibits platelet function, the risk of GI bleeding is higher than with either medicine alone. This is a clinically relevant interaction for people on antidepressants who regularly take aspirin for headaches. Paracetamol is a safer analgesic choice for people on SSRIs or SNRIs.
How quickly does aspirin work for pain?
Aspirin reaches peak plasma concentrations within 20 to 40 minutes of an oral dose. Pain relief is typically noticeable within 30 to 60 minutes for most presentations. For the emergency MI indication, chewing the tablet accelerates buccal absorption. The onset of pain relief is broadly comparable to ibuprofen.
Can aspirin be used for a sore throat?
Yes. Sore throat is a licensed indication. Aspirin's anti-inflammatory and analgesic action addresses the inflammation and pain of acute pharyngitis. If your sore throat is severe, persists for more than a few days, is accompanied by a high fever, or makes swallowing difficult, seek medical assessment to rule out bacterial infection requiring antibiotic treatment.
What happens if I take too much aspirin?
Seek emergency medical attention immediately, even if you feel well. Aspirin overdose (salicylate poisoning) can cause tinnitus, dizziness, nausea, vomiting, confusion, rapid breathing, and, in severe cases, metabolic acidosis and death. Serious harm can develop before obvious symptoms appear. Call 999 or go to your nearest emergency department and take the packaging with you.
Is aspirin safe for long-term daily use?
At 300mg analgesic doses, long-term daily use is not recommended without medical supervision. It significantly increases the risk of gastric ulceration, GI bleeding, and salicylate accumulation. Low-dose aspirin at 75mg taken daily for cardiovascular prevention is a separate clinically supervised use. If you feel you need aspirin daily for pain control, speak to your GP about whether a longer-term pain management plan is appropriate.
Disclaimer: This article is for general information only and isn’t a substitute for personal medical advice, diagnosis, or treatment. Always check with a GP, pharmacist, or specialist before starting a new supplement if you have a medical condition or take regular medicines.
More than a prescription: our community
At Courier Pharmacy, we show up for healthcare even when nothing is being purchased. Our free fortnightly drop-in clinics and talks at Insomnia, Derby run every other fortnight from 10 am to 12 pm. Pain management, NSAID safety, analgesic interactions, and understanding which OTC products suit your medical history are topics we cover regularly.
Whether you have a specific question about aspirin, want to understand how it fits with other medicines you take, or simply want to be in a space where health questions are taken seriously without any pressure to buy anything, you are welcome.
Learn more about our community talks and find the next session date at courierpharmacy.co.uk. Healthcare should be accessible, not just when you are buying. We mean that.
How this content was created
Written by the Courier Pharmacy editorial team and reviewed by a GPhC-registered pharmacist. Grounded in the latest NHS, NICE, BNF and EMC guidance, peer-reviewed studies, and the real questions patients bring to our drop-in clinics in Derby.
