4 Medication Storage and Interactions

Store medicines safely

Medicines may lose effectiveness if stored incorrectly, and medicines within reach can cause accidental poisoning. Follow the storage directions on each label or patient leaflet: some medicines need refrigeration, while others must be protected from moisture, light, or heat.

Unless instructed otherwise, keep medicines in a cool, dry place—not a humid bathroom or a hot car. Store them in their labeled, child-resistant containers, securely closed and out of children’s and pets’ sight and reach. Do not leave medicines in purses, bags, or on counters.

Check expiration dates. If a medicine may have been exposed to extreme temperatures, ask a pharmacist what to do.

Dispose of unused medicines

Use a take-back location or prepaid mail-back option when available. If neither is readily available, check the medicine’s label and the current FDA flush list. Flush only medicines listed there.

For most other medicines, FDA advises removing them from their original containers, mixing them with an undesirable substance such as used coffee grounds or cat litter without crushing tablets or capsules, sealing the mixture in a container, and placing it in household trash. Scratch out personal information on empty packaging. Follow product-specific instructions for medicines such as patches, and ask a pharmacist if disposal directions are unclear.

Recognize and check medication interactions

A medication interaction occurs when a medicine, food, drink, supplement, or another medicine changes a drug’s effects or the amount of drug in the body. The result may be stronger side effects, reduced effectiveness, or another harmful effect. Interactions can be specific to a particular drug, so do not assume that every medicine in a class has the same restriction.

Keep an up-to-date list of all prescription medicines, over-the-counter (OTC) products, vitamins, herbs, and other supplements, including doses. Share the list with the pharmacist and other clinicians, and mention usual foods and alcohol use.

Before adding, stopping, or changing a medicine or supplement, check the product information and ask a pharmacist or prescriber. Do not stop a prescribed medicine or change its dose on your own.

Consider foods, medicines, and supplements

The relevant restriction or risk depends on the particular medicine or product. Check labels and ask a pharmacist or prescriber about the specific medicine rather than assuming that all medicines in a category have the same interaction.

Check specific food, medicine, and supplement risks

Grapefruit can raise or lower the amount of certain medicines absorbed. This applies to some drugs, not all drugs in a category. Follow the medicine’s label and ask whether grapefruit or other juices matter for that particular medicine.

Combining products with similar effects can increase harm. For example, taking sedating medicines together may increase drowsiness and fall risk. Check prescription and OTC labels, including cold and pain products, rather than relying on brand names alone.

St. John’s wort can reduce the effects of several medicines and can also contribute to serious interactions with some antidepressants. Tell the care team about supplements, including those sold without a prescription.

Check alcohol-related risks

Alcohol can change how some medicines work or intensify effects such as drowsiness and impaired coordination. The risk varies by medicine and amount consumed. Check the label and ask a pharmacist or prescriber whether alcohol must be avoided; there is no single waiting period that is safe for every medicine.

Confirm the plan with teach-back

A clinician can use teach-back to check whether a patient understands the interaction plan: ask the patient to explain which foods, medicines, supplements, or alcohol they should avoid or check, and whom they will contact before making a change.

For example, a patient planning to start St. John’s wort while taking a prescription medicine should contact a pharmacist or prescriber first and provide a complete list of medicines and supplements. They should not independently change the prescription.