Aggrenox Explained: Uses, Dosage, Side Effects & FAQs

Sep, 21 2025

TL;DR

Aggrenox combines low‑dose aspirin with dipyridamole to lower the risk of another stroke after a TIA or minor stroke.
Standard regimen: two tablets (each 25mg aspirin+200mg dipyridamole) twice daily, or one extended‑release tablet once daily.
Common side effects: headache, dizziness, upset stomach, and mild bleeding; serious bleeding is rare but requires immediate medical attention.
Take it with food, stay hydrated, and avoid other NSAIDs unless your doctor says otherwise.
Ask your GP about interactions with warfarin, clopidogrel, or any herbal supplements you use.

What Aggrenox Is and How It Works

When you hear the name Aggrenox, think of a two‑in‑one pill that brings together aspirin and dipyridamole. Aspirin is the well‑known antiplatelet that blocks the enzyme COX‑1, reducing the sticky clumps of platelets that can block blood vessels. Dipyridamole does a different job - it keeps blood vessels relaxed and boosts the amount of a natural blood‑thinning substance called adenosine.

By pairing these actions, Aggrenox attacks clot formation from two angles. This double strike is why doctors often choose it for people who have already suffered a transient ischemic attack (TIA) or a non‑disabling stroke. The goal isn’t to treat an acute event; it’s to keep another one from happening.

In the UK, the Medicines and Healthcare products Regulatory Agency (MHRA) has approved Aggrenox for secondary stroke prevention. The evidence comes from large trials such as the ESPS‑2 (European Stroke Prevention Study 2) and the ESCAP (European Stroke Prevention Study - Aspirin Controlled) which showed a roughly 20% reduction in recurrent stroke when patients took the combination versus aspirin alone.

When and Why Doctors Prescribe Aggrenox

Typical scenarios include:

A 68‑year‑old who survived a minor ischemic stroke and wants to cut the odds of another hit.
A middle‑aged patient with a history of TIA who also has hypertension and high cholesterol.
Someone who can’t tolerate clopidogrel or newer antiplatelet agents due to side effects.

The drug is not a first‑line choice for people who haven’t had any cerebrovascular event. It’s specifically for secondary prevention - that is, stopping a repeat problem.

Doctors will also check a few basics before writing the prescription:

Bleeding risk: active ulcers, recent surgeries, or a known bleeding disorder usually rule out Aggrenox.
Allergy profile: anyone allergic to aspirin or dipyridamole should avoid it.
Kidney function: severe renal impairment can change how dipyridamole is cleared.

Pregnant or breastfeeding women are generally advised to stay clear of Aggrenox because aspirin, even at low doses, can affect fetal platelet function.

How to Take Aggrenox Safely: Dosage, Timing, and Practical Tips

There are two formulations you’ll encounter at UK pharmacies:

Immediate‑release tablets: each tablet contains 25mg aspirin+200mg dipyridamole. The usual schedule is one tablet twice a day, about 12hours apart.
Extended‑release tablet: combines the same amounts but releases slowly over 24hours. Patients take one tablet once daily, typically in the evening.

Key administration pointers:

Swallow tablets whole with a full glass of water - don’t crush or chew.
Take with food, especially the immediate‑release version, to minimise stomach upset.
Maintain a consistent schedule; missing a dose by a few hours is okay, but double‑dosing to catch up is not.
Stay well‑hydrated - dipyridamole can cause mild dehydration, which may intensify headaches.

If you accidentally skip a dose, simply take the next scheduled one. If you’re close to the next dose, skip the missed tablet - you don’t want two doses within a short window because that raises bleeding risk.

Interaction alerts you should keep in mind:

Other NSAIDs (ibuprofen, naproxen) increase bleeding odds.
Anticoagulants like warfarin, dabigatran, or apixaban require tighter monitoring - your GP may adjust the INR target or pause one of the drugs.
Herbal supplements such as ginkgo, garlic, or high‑dose fish oil can also affect clotting.

Regular blood work isn’t mandatory for most people, but your clinician might ask for a full blood count after three months to check platelet levels, especially if you’re on other blood‑thinners.

Side Effects, Warning Signs, and Frequently Asked Questions

Like any medication, Aggrenox isn’t free of unwanted effects. The most common (affecting up to 15% of users) are:

Headache - often a throbbing sensation that eases after a few days.
Dizziness or light‑headedness, especially when standing quickly.
Gastro‑intestinal discomfort: nausea, indigestion, or mild abdominal pain.
Bleeding gums or easy bruising - a sign that platelet inhibition is working, but watch for anything beyond that.

Serious, though rare, warnings include:

Severe gastrointestinal bleeding - black or bloody stools, vomiting blood, or sudden weakness.
Allergic reactions - rash, itching, swelling of face or throat, difficulty breathing.
Signs of stroke despite therapy - sudden numbness, trouble speaking, vision changes - call emergency services immediately.

Below are concise answers to the questions most people type into search engines after hearing the drug name.

Can I take Aggrenox with warfarin?: Yes, but only under close supervision. Your doctor will monitor INR more frequently and may adjust the warfarin dose.
Is Aggrenox safe for people over 80?: Age alone isn’t a barrier, but older adults have higher bleeding risk. Starting with the lowest effective dose and regular check‑ups is prudent.
What should I do if I develop a severe headache?: Contact your GP right away. Sometimes the headache signals low blood pressure from dipyridamole, and a dose adjustment may be needed.
Can I drink alcohol while on Aggrenox?: Moderate alcohol (up to one drink a day) is usually okay, but heavy drinking amplifies bleeding risk.
Do I need to stop Aggrenox before surgery?: Yes. Typically, stop 7‑10days prior to any elective procedure; discuss timing with your surgeon and GP.

Remember, the best way to stay safe is an open conversation with your healthcare team. Keep a list of all medicines, over‑the‑counter drugs, and supplements you use, and bring it to every appointment.

Next Steps and Troubleshooting

If you’re starting Aggrenox, mark the first few doses on a calendar or set phone reminders. Notice any new symptoms and note their timing - this info helps your doctor decide if an adjustment is needed.

Should you experience persistent headaches or gastrointestinal upset, try taking the tablet with a larger meal or a light snack. If symptoms linger beyond a week, call your GP - they may switch you to the extended‑release version or suggest a proton‑pump inhibitor to protect your stomach.

For anyone who has missed several doses in a row, don’t restart at a higher dose. Instead, schedule an appointment to review why the schedule fell through; sometimes a different formulation or once‑daily dosing fits a busy lifestyle better.

Finally, keep an eye on your lifestyle factors: a balanced diet, regular exercise, and blood‑pressure control all reinforce the protective effect of Aggrenox. Medication works best when paired with a heart‑healthy routine.