Tests & medicines
What your lab report means line by line, and how to use medicines safely.
What do high liver enzymes on my blood test mean?
Raised ALT or AST means liver cells are irritated, not that the liver is failing. The everyday causes dominate: fatty liver, alcohol, recent viral illness, some medicines and supplements, and vigorous exercise before the blood draw.
What is a normal eGFR and when should I worry?
eGFR estimates kidney filtering from your creatinine, age and sex. Above 90 is full function, 60 to 89 is mildly reduced and common with age, and persistently below 60 for three months defines chronic kidney disease.
My TSH is high. What does that mean?
TSH is the pituitary shouting at a sluggish thyroid: high TSH usually means the thyroid is underperforming. With low T4 it is overt hypothyroidism; with normal T4 it is subclinical, a gray zone often just watched.
What actually happens if my vitamin D is low?
Real deficiency thins bones over years, aches muscles and bones, saps energy, and in severe cases softens bone outright. Indoor lives, covered clothing, darker skin at high latitudes and older age drive most of it.
What are the signs of low B12?
B12 deficiency builds slowly: fatigue and pallor from anemia, then the nervous system, tingling hands and feet, unsteady walking, memory dulling, low mood, sometimes a sore smooth tongue. Nerve damage can arrive before anemia does.
Why would my platelets be low?
Platelets dip with viral infections, alcohol, some medicines, liver disease, pregnancy, and immune conditions; lab clumping artifacts also fake low counts, which a repeat test exposes.
Do I really need to fast before a blood test?
Depends on the test. Fasting glucose needs 8 to 12 hours with water allowed. Modern cholesterol testing mostly no longer requires fasting, though triglycerides read truer fasted. HbA1c, thyroid, kidney and blood counts do not care when you ate.
Can I take paracetamol and ibuprofen together?
For most healthy adults, yes: they work differently and combine safely for short-term pain, either together or staggered. Respect each label's daily maximum and count combination cold-and-flu products, which hide paracetamol.
Why won't my doctor give antibiotics for my cold?
Colds and flu are viruses, and antibiotics kill only bacteria; taking them for a virus adds side effects and breeds resistant bacteria while the cold runs its identical course. Green mucus does not mean bacterial, it means the immune system is working.
How common are statin side effects really?
Blinded trials tell the honest story: muscle symptoms occur at nearly the same rate on statins as on placebo, a far cry from internet lore. True statin muscle damage is rare, and serious liver problems rarer.
What does a CRP blood test measure?
CRP is a smoke detector for inflammation anywhere: infections, flares of autoimmune disease, injury and more all raise it. It shouts that something is happening without saying what or where.
Can I stop my antidepressant now that I feel better?
Feeling better is the medicine working, and stopping at the first good stretch is the classic relapse recipe: guidelines suggest six to twelve months of feeling well before tapering after a first episode, longer after repeats.
My uric acid is high. Do I have gout?
Not automatically: most people with high uric acid never develop gout, and a hot swollen joint is what makes the diagnosis, classically the big toe at 2 am, red and exquisitely tender.
What is the difference between HbA1c and a glucose test?
Glucose is a snapshot, the sugar in your blood this minute, swayed by the last meal, stress and sleep. HbA1c is the film: sugar has been sticking to red blood cells for their three month lifespan, and the test reads that accumulated coating.
Can supplements damage your liver?
Yes, and it is increasingly common: herbal and dietary supplements now cause a meaningful share of drug-induced liver injury. Repeat offenders include green tea extract in weight loss pills, bodybuilding blends with hidden steroids, high-dose turmeric extracts, and multi-ingredient fat burners.
Does it matter what time I take my blood pressure medicine?
Consistency beats clock time: the same time daily keeps levels steady, and the best-known trial found morning versus evening made no difference to heart outcomes. Some medicines pick their own slot, diuretics in the morning to spare your night, anything that causes dizziness at bedtime.
What is ferritin and why does it matter more than hemoglobin?
Ferritin is the iron warehouse; hemoglobin is the delivery trucks. Stores empty long before deliveries fail, so you can be significantly iron deficient, tired, breathless, shedding hair, restless legs, with perfectly normal hemoglobin. Testing only hemoglobin misses that entire stage.
Are generic medicines as good as branded ones?
Yes. Generics must prove the same active ingredient, dose and absorption profile as the original, and decades of surveillance keep confirming equivalence; most doctors take generics themselves. The price difference funds marketing and recovered research costs, not quality.
What does protein in my urine mean?
Healthy kidney filters hold protein back, so protein in urine can be an early kidney whisper, or completely benign: fever, hard exercise, dehydration and standing all day each spill protein temporarily.
Can I drink alcohol while on antibiotics?
For most antibiotics, moderate alcohol does not break the medicine; the blanket ban is folklore. The hard exceptions: metronidazole and tinidazole, where alcohol triggers flushing, vomiting and pounding heart, wait 48 to 72 hours after finishing, and a few others where doctors advise abstaining.
Why did my doctor order thyroid antibodies?
Antibodies answer the why behind an odd TSH: high TPO antibodies point to Hashimoto's, the immune system slowly dialing the thyroid down, the most common cause of hypothyroidism. Different antibodies confirm Graves disease when the thyroid runs hot.
Why does every doctor keep asking for my full medication list?
Because interactions and duplications hospitalize people daily: two doctors innocently prescribing similar drugs, a supplement blocking an antibiotic, a painkiller quietly straining kidneys already on a diuretic. The list is the collision map.
What does it mean if my eosinophils are high?
Eosinophils are the allergy-and-parasite wing of white cells. Mild elevations most often track allergic conditions, asthma, eczema, hay fever, or medication reactions; parasitic infections matter with relevant travel or exposure; rarer causes exist for persistent high counts.
Are annual full-body checkup packages worth it?
The glossy packages oversell: whole-body scans and forty-test panels in symptomless people mostly find harmless quirks that trigger anxiety and follow-up cascades, while missing the point of screening.
What should I ask before starting any new medicine?
Five questions cover most trouble: What is this for and how will we know it works? How and when exactly do I take it? What are the common side effects and which rare one should make me call? How does it sit with my other medicines and supplements? How long will I be on it and what is the exit plan?