They are two of the staples of any home first-aid kit. Whether for a headache, muscle pain, fever or the flu, we have all turned to ibuprofen and paracetamol at some point for our health. But do we really know which is best for each situation?
Pharmacist Meritxell Martí answers some of the most frequently asked questions about the dilemma: when to choose paracetamol, when to opt for ibuprofen, and why combining them isn't the best approach.
Understanding how they work and their potential risks is key to using them safely and effectively. First and foremost, remember that both, while commonly available, are medications and should not be used without caution.
The expert sends a clear message: self-medicating carries genuine risks, such as taking an incorrect dose or using the medication for too long.
With these warnings in mind, it is worth noting that while both ibuprofen and paracetamol are effective for fever and pain, they work in different ways.
© Getty ImagesParacetamol (Acetaminophen) explained: Uses and mechanism
- Paracetamol is known as acetaminophen in the US.
- It's recommended as symptomatic treatment for cases of mild to moderate pain, and to reduce fever.
- It functions primarily in the central nervous system, where it is believed to inhibit specific enzymes (such as COX-3) to block pain signals.
Ibuprofen explained: Uses and mechanism
- While ibuprofen is effective for general pain relief, it is specifically recommended when that pain is accompanied by inflammation. Therefore, it is the preferred choice for conditions such as muscle aches, menstrual cramps and dental pain, as well as for lowering a fever.
- It works by inhibiting the COX-1 and COX-2 enzymes, which in turn reduces inflammation in the body.
© Getty ImagesIbuprofen vs paracetamol: How to choose the right one
As a general rule of thumb (keeping in mind that individual contraindications always apply) the expert offers the following guide for choosing between the two:
- Paracetamol: Best for fever or pain without inflammation.
- Ibuprofen: Best for fever or pain with inflammation.
However, there are important nuances to consider. Beyond the obvious need to avoid active ingredients to which you are allergic, people with sensitive stomachs and pregnant women should opt for paracetamol.
For children, administration in either case should be done under medical guidance. Furthermore, combining the two medications should never be done without specific instruction from a doctor.
© Getty ImagesDrug Interactions: Who should NOT take ibuprofen or paracetamol?
While your doctor is the best person to evaluate your specific medical needs, Martí highlights several key contraindications and interactions that everyone should be aware of before opening the medicine cabinet.
Paracetamol (Acetaminophen)
Paracetamol is generally considered the safer option for the stomach, but it is strictly processed by the liver. Therefore, specific cautions apply:
- It must be used with extreme caution by anyone with liver issues, including hepatitis, liver cirrhosis, or fatty liver disease, due to the risk of hepatotoxicity (liver damage).
- Avoid or consult a doctor in cases of severe malnutrition or during prolonged fasting periods.
- Caution is advised in cases of severe kidney failure.
What not to mix with paracetamol:
- Alcohol: Never combine with alcohol, as this significantly increases the risk of liver damage.
- Anticoagulants: Long-term use of paracetamol can potentiate the effect of blood thinners, increasing bleeding risk.
- Epilepsy medication: Drugs such as phenytoin or carbamazepine induce liver enzymes which can increase the toxicity of paracetamol.
- Other Medications: Avoid combining with isoniazid or rifampicin (TB drugs) due to liver stress, or zidovudine (HIV medication) due to risks of blood toxicity.
© iStockIbuprofen
As an anti-inflammatory, ibuprofen should be avoided in the following cases:
- People with gastric ulcers, gastritis, or acid reflux should avoid it, as it damages the stomach lining and can cause bleeding.
- Avoid in cases of kidney failure, as it reduces blood flow to the kidneys.
- Those with hypertension or cardiovascular disease should be cautious; ibuprofen can raise blood pressure, especially at high doses.
- It can trigger bronchospasm in asthma patients who have a known sensitivity to aspirin or NSAIDs.
- In case of pregnancy, ibuprofen should be avoided (unless prescribed by a doctor), and is strictly contraindicated from the third trimester onwards due to risks to the foetus.
© Getty ImagesWhat not to mix with ibuprofen:
- Blood pressure medication: It should not be combined with antihypertensives or diuretics, as it can reduce their effectiveness and damage the kidneys.
- Anticoagulants: Never combine with blood thinners; ibuprofen increases the blood-thinning effect and the risk of internal bleeding.
- Corticosteroids: Avoid mixing with oral steroids (like prednisone) as this dramatically increases the risk of stomach ulcers.
- Lithium & Methotrexate: Ibuprofen interferes with the elimination of these drugs, leading to potentially toxic levels in the blood.
In any case, your GP is the only one who can fully evaluate your medical history to decide which medication is safe for you.
Unlike ibuprofen, paracetamol can be taken with or without food, as it is generally gentle on the gastric system
Correct dosage & timing
Martí points out that while standard doses are available over the counter (typically 500 mg for paracetamol and up to 400 mg for ibuprofen), higher-strength formulations usually require a doctor’s prescription.
The general advice is to adhere to a schedule of taking a dose every 6 to 8 hours, though you should always follow any specific instructions given by your GP.
A key difference lies in how they interact with your stomach:
- Paracetamol can be taken with or without food, as it is generally gentle on the gastric system.
- Ibuprofen, however, should always be taken with meals or immediately after eating to prevent stomach irritation.
© Getty ImagesCan you take them together?
"You should not take both at the exact same time unless medically indicated," notes Martí. "If you are advised to alternate them, you must leave a gap of at least 3 or 4 hours between each dose." She reiterates the golden rule: choose paracetamol if you have a sensitive stomach, and ibuprofen if you are dealing with inflammation.
"Both medications are available in a wide variety of forms: tablets, capsules, soluble sachets, syrups, suppositories and even topical gels," she explains.
She adds that there are also compound formulas containing additional ingredients like caffeine, codeine or antihistamines, though regulations for buying these will vary depending on the specific ingredients, and where you are located.
