Dosage: How to Read, Measure, and Use Medications Safely

Medication errors are common, but many are preventable with a few clear steps. If you want to get dosage right — for yourself, a child, or an elderly relative — focus on the label, the units, and the measuring tool. That alone stops a lot of mistakes.

First, read the label every time. Look for the active ingredient, the strength (for example 250 mg or 0.5 mg), the form (tablet, liquid, inhaler), and the dosing instructions. Don’t rely on memory. Labels matter because brand names can hide different strengths and formulations.

Watch the units. Milligrams (mg), micrograms (mcg), international units (IU) and milliliters (mL) are not interchangeable. Quick conversion facts to remember: 1 mg = 1,000 mcg; 1 teaspoon = 5 mL; 1 tablespoon = 15 mL. Those little numbers change the meaning of a dose.

Quick dosing rules to follow

Use the right tool. For liquids, use an oral syringe or dosing cup that came with the medicine. Kitchen spoons are unreliable. For inhalers, follow the priming and counting instructions so you know how many puffs you’ve used. For injections or patches, follow the product and clinician instructions strictly.

Know how pediatric doses are calculated. Many children’s medicines use weight-based dosing (mg/kg). That means you multiply the milligram dose by the child’s weight in kilograms. Example math: if a drug is 10 mg/kg and the child weighs 15 kg → 150 mg. That’s a math step many parents miss, so double-check with a provider or pharmacist if you see a mg/kg instruction.

Adjustments matter. People with kidney or liver problems often need different doses. Older adults may need lower doses, too. If you have any chronic disease or take multiple meds, check with a clinician before changing doses — interactions and organ function change how drugs work.

When to check and what to watch for

If instructions are unclear, don’t guess. Call the pharmacy, contact your prescriber, or use a trusted medical site for cross-checking. Watch for common red flags: a dose that sounds very large, different instructions on two labels, or a change in formulation (immediate vs. extended release). Ask specifically: is this pill scored? Can I split it? Is the liquid concentration different from what I used before?

Know the signs of too much or too little. Overdose signs differ by drug but commonly include severe drowsiness, fast or irregular heartbeat, confusion, breathing trouble, or severe stomach upset. If you suspect overdose, seek emergency care. If a medicine isn’t helping or side effects start, call your clinician; don’t just increase the dose.

Finally, document doses. Keep a simple log for complex regimens — date, time, dose, and any side effects. It keeps everyone on the same page and makes clinic visits easier. Small habits like these cut risk and keep treatment on track.