What should you know about a BMP blood test?

The panel commonly includes sodium, potassium, chloride, bicarbonate, glucose, calcium, urea nitrogen and creatinine. These results can give clues about hydration, acid-base balance, blood sugar and how the kidneys are filtering waste. The panel is interpreted with symptoms, medicines and previous results; one abnormal value does not identify a cause by itself.

Kidney-related results can be affected by fluid loss, muscle mass, diet and medicines. A BMP is different from a full blood count, which looks mainly at blood cells.

Ask whether fasting is needed, because the glucose result may be interpreted differently after eating. Take your usual medicines unless the requesting clinician gives different instructions, and mention supplements, vomiting, diarrhoea or recent heavy exercise. The sample is taken from a vein and may leave temporary tenderness or bruising.

Keep the report and compare it with the reference range printed by that laboratory. If a result is outside range, arrange the recommended review rather than changing medicines yourself.

Seek prompt advice for very little urine, worsening swelling, repeated vomiting, confusion, marked weakness or symptoms of high or low blood sugar. Emergency help is appropriate for collapse, severe breathing difficulty, chest pain or a seizure. These symptoms require clinical assessment rather than interpretation of a result alone.

Which BMP values are you checking in my case? Do I need to fast or repeat the sample? Could any of my medicines affect the result? What symptoms should prompt me to contact the practice?