Drug interaction

A drug interaction occurs when another medicine, substance or sometimes food changes how a medicine works or affects safety. The result may be stronger effects, reduced effectiveness or additional unwanted effects. Interactions can involve prescription medicines, over-the-counter products, supplements and alcohol, so a complete list matters during a medication review.

Does natural mean there is no interaction risk?

No. Herbal and complementary products can affect prescribed treatment. A product being available without a prescription does not make it suitable in every combination. Tell the doctor or pharmacist about everything you use, including occasional products and substances you may not think of as medicines.

Bring packaging or clear photographs when names are uncertain. Include recent changes and how often you take each product. A list that only includes long-term prescriptions may miss the combination responsible for a new symptom.

For the Australian guidance behind this explanation, see Healthdirect Australia: Medicines and alcohol - Healthdirect Australia.

How are interactions checked?

A clinician or pharmacist considers the specific products, doses, timing, health conditions and the seriousness of any potential interaction. An online checker can flag possibilities, but cannot fully assess your individual circumstances or decide which treatment is most important.

Ask whether the combination should be avoided, monitored or managed in another way. Simply taking products at different times does not resolve every interaction. Do not independently stop an essential treatment or change the dose because an app displays a warning.

What if I develop symptoms?

Contact a pharmacist or prescriber promptly if a new symptom follows a treatment change. Severe breathing difficulty, collapse, major bleeding or reduced consciousness requires 000. For suspected poisoning or an accidental extra dose, the Poisons Information Centre can advise on 13 11 26.

Doccio's prescription service can be a starting point for an appropriate review. The doctor may need records, tests or contact with your usual clinician before deciding whether a requested combination is safe.

Where to go next

Read prescription consultations to understand the relevant service. A doctor decides whether a consultation, examination, referral or another pathway is appropriate for your situation.