Your medication list: how to keep it right and why it matters for interactions

Almost every consultation starts with the same question: "What medications do you take?" And almost every answer is incomplete. The magnesium supplement is forgotten, so are the eye drops, the "stomach" pill taken when needed, the contraceptive, yesterday's ibuprofen. Not out of carelessness: because nobody keeps count, and the list exists only in memory.

The problem is not bureaucratic. Interactions between medications, supplements and food are one of the frequent and avoidable causes of hospital admissions, especially after 65 and in anyone taking five or more medications. And the only way to check them is a complete list, with doses, that the doctor and the pharmacist can see. This guide explains what the list must contain, why the active substance matters more than the brand name, how interaction checking works and how to keep the list current without effort.

A necessary warning before anything else: this guide does not say which medications to take or not take. Do not change, stop or add anything on the basis of it; talk to your doctor or pharmacist.

What the list must contain

For everything you take, six pieces of information:

1. The name: the brand (what is on the box) and, more importantly, the active substance (what is written in small letters underneath). Nurofen, Advil and Brufen are all ibuprofen.
2. The dose: 500 mg, 10 mg, 20 µg. Not "one tablet"; the tablet can be 5 or 20 mg.
3. How and how often: in the morning, twice a day, when needed, "every 12 hours", with food or on an empty stomach.
4. Why: for blood pressure, for pain, for sleep. A new doctor understands the list much faster when they see the reason.
5. Since when and, if applicable, until when: a 7-day antibiotic and a chronic treatment since 2019 are not the same thing.
6. Who prescribed it: the family doctor, the cardiologist, yourself (over the counter).

And the categories almost always forgotten:

• Over-the-counter medicines: anti-inflammatories (ibuprofen, diclofenac), paracetamol, antacids, herbal sleep aids, antihistamines.
• Supplements and herbs: vitamin D, magnesium, iron, omega-3, St John's wort, ginkgo, concentrated garlic, green tea capsules. Some interact seriously (St John's wort with contraceptives and antidepressants, for example).
• Contraceptives and hormone therapy.
• Drops, sprays, creams, patches, inhalers. They have an active substance and a dose like any tablet.
• Occasional injections: monthly vitamin B12, the six-monthly osteoporosis injection.
• What you take "when needed": migraine, allergy, pain. Note how often "when needed" actually is.

Why the active substance matters more than the name

The same medication has dozens of brand names, different from country to country and manufacturer to manufacturer. A doctor in Germany does not know what "Nurofen Forte" from Romania is, but knows immediately what "ibuprofen 400 mg" is. And the reverse: two boxes with different names can contain the same substance, and whoever takes both doubles the dose without knowing. It happens often with paracetamol, present in dozens of "cold and flu" combinations.

To make the list understood anywhere, there is the ATC classification (Anatomical, Therapeutic, Chemical), managed by the World Health Organization: every active substance has a unique code (ibuprofen: M01AE01), organised by the organ it acts on and the therapeutic class. An app that stores the ATC code, not just the name on the box, can:

• recognise that two different boxes are the same medication;
• check interactions by substance, not by name;
• show the list in a format any medical system, in any country, reads (in FHIR records, medications are coded exactly like this).

When you note a medication, note what is written in small letters: the substance and the dose. The big name on the box is a detail.

How interactions work, briefly

You do not need to know them all; you need to know they exist and that they are checked against the list, not from memory. The main types:

Medication with medication. One can strengthen the other (two sedatives), weaken it (an antacid that blocks the absorption of an antibiotic), or together they can have a side effect neither has alone (an anti-inflammatory plus an anticoagulant: bleeding risk). A classic to check every time: any new medication in someone taking anticoagulants.

Medication with supplement or herb. St John's wort reduces the effect of many medications, including contraceptives. Ginkgo and high doses of omega-3 can increase bleeding risk with anticoagulants. Calcium and iron reduce the absorption of some antibiotics and of thyroid hormones if taken at the same time.

Medication with food. Grapefruit raises the level of some statins and other medications. Foods rich in vitamin K (cabbage, spinach) influence warfarin. Alcohol interacts with sedatives, with high-dose paracetamol and with many others.

Medication with condition. Not an interaction in the strict sense, but just as important: anti-inflammatories in someone with weak kidneys or an ulcer, decongestants in someone with high blood pressure, some antibiotics in someone with heart rhythm problems.

Who checks: the doctor when prescribing (if you give them the full list), the pharmacist when dispensing (pharmacies have systems that alert on known interactions, but only for what is in their system) and, increasingly, the software in medical record apps. None of them sees what is not on the list.

How to keep the list current

The rule is the same as for the rest of the medical record: every change goes into the list the day it happens.

• New prescription: scan it or photograph it; good apps read the substance, dose and schedule straight from the document. Add the reason and the doctor.
• New over-the-counter box from the pharmacy: scan it. The barcode or the box gives the substance and the dose.
• Dose changed: do not overwrite; close the old entry and start a new one. A year on, the doctor will want to know when the dose changed and why.
• Treatment finished: mark it as finished, with the date. Completed antibiotics do not disappear from the history; they leave the current list.
• Allergy or adverse reaction: note the medication, what happened and how severe. It goes into the allergy list too, not just the diary.

For chronic treatments, adherence matters as much as the list: a medication taken on 60% of days is not the treatment the doctor thinks you are on. Reminders and ticking off doses are not "for old people"; they are for anyone taking more than one medication a day. And when you do not take a medication because something bothers you, write that down, do not omit it. The doctor can change the dose or the medication; they cannot fix what they do not know.

How to share it with your doctor and pharmacist

The list has value only if it reaches whoever prescribes. Three ways, from the simplest:

1. On paper or on screen, at the consultation. The full list, with doses, printed or on your phone. The doctor reads it in 30 seconds and compares it with what is in their system.
2. As part of the medical summary. The International Patient Summary (IPS) has current medication as a required section, ATC-coded, so readable in any system. If your app generates an IPS, the list goes with it.
3. Through direct access, with consent. Your family doctor or pharmacist gets access to your list from the record, for a limited period, and sees changes as you make them. It is the best option for complex chronic treatments.

A good habit once a year, especially over 65 or with more than five medications: ask for a medication review with your family doctor or pharmacist. Every entry is checked: is it still needed, is the dose right, is there a safer alternative, can anything be dropped. It is called "deprescribing" and it is often the best medical intervention of the year.

How Anpheros helps

Anpheros Daily keeps the medication list as ATC-coded FHIR resources: you photograph the prescription or the box and the app extracts the active substance, the dose and the schedule, with the medication linked to the source document. Doses are ticked off day by day, reminders come at the right time, and the history keeps every dose change and every finished treatment. The list goes automatically into the IPS summary and the emergency card, and the doctor or pharmacist you give access to sees it up to date. Supplements and over-the-counter medicines have the same fields as prescribed ones, precisely so they do not stay off the list.

Frequently asked questions

Do I need to put vitamins on the list too?

Yes. Supplements have active substances and they interact: iron and calcium with thyroid hormones and some antibiotics, St John's wort with contraceptives and antidepressants, ginkgo and high-dose omega-3 with anticoagulants. The doctor cannot take them into account if they do not see them.

Can I check interactions myself online?

You can use online checkers to understand and to prepare your questions, not to decide. They do not know your dose, your kidney function, your age or why you take each medication, and many alerts are theoretical. The decision to change anything stays with your doctor or pharmacist.

What if I no longer know why I take a medication?

Note it as "reason unknown" and ask at the next consultation. Do not stop it yourself: some medications (for blood pressure, for the heart, corticosteroids, antidepressants) must not be stopped abruptly.

How often should the list be reviewed?

At every change, immediately; in full, once a year or at any hospital admission and discharge. After an admission, the list almost always changes, and "transition" errors between hospital and home are among the most frequent.

Do "when needed" medications go on the list?

Yes, marked "when needed" and with the real frequency. "Ibuprofen 400 mg, when needed, about three times a week" tells the doctor something important about pain and about the risk to stomach and kidneys; "nothing regular" tells them nothing.