Sudden severe headache, weakness, speech problems, fever or neck stiffness are warning signs.

A headache reaching maximum intensity within seconds, following a head injury, or accompanied by one-sided weakness, vision or speech changes, confusion, seizures, fever and neck stiffness needs urgent assessment. A clear change in the pattern of previous headaches also deserves medical review.
Medical principle
Even non-prescription medicines can cause side effects and interactions. Medicine selection should consider the likely cause, age, pregnancy, liver and kidney disease, a history of stomach ulcers and other medicines.
Practical steps that may help
- Keep the names, doses and timing of all medicines and supplements on your phone or on paper.
- Check for products containing the same active ingredient to avoid unintended duplicate doses.
- Do not take someone else’s antibiotics, sedatives or other medicines; use medicines exactly as directed.
When should you seek medical care?
Reduced awareness, seizures, breathlessness, swelling of the face or throat, a sudden very severe headache, fever with neck stiffness, or severe unusual pain require immediate action.
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