Preparing for Your First Bloodwork: The 7-Day Countdown

Biotin (vitamin B7): Stop 7 days before. Biotin at doses above 5 mg/day (common in hair/nail supplements and some multivitamins) interferes with immunoassay-based tests — it can falsely lower TSH, falsely lower troponin, and falsely elevate or suppress other hormone values. If you're taking a standalone biotin supplement or a high-dose B-complex, stop 7 days out. Standard multivitamins with <1 mg biotin are fine to continue.

High-dose zinc (>25 mg/day): Stop 5–7 days before if possible. Supraphysiologic zinc can transiently affect testosterone assays at some labs. Zinc in a standard multivitamin (8–15 mg) is not a concern. Iron supplements: continue if prescribed. Pre-draw iron status tests (ferritin, serum iron, transferrin) are best drawn after a period of not taking iron tablets for 24 hours — ask Dr. Nikola if ferritin is in your panel.

Exogenous hormones (including DHEA, pregnenolone, testosterone boosters): If you are testing hormone levels, these should ideally be stopped or at minimum noted on your intake form. DHEA supplementation elevates DHEA-S. OTC testosterone boosters with herbal extracts (ashwagandha, tongkat ali) don't significantly affect the assay but should be noted for context.

Alcohol within 48–72 hours of a blood draw has the most significant impact on: triglycerides (alcohol drives hepatic TG synthesis — even 2–3 drinks the night before can raise fasting TG by 30–50%), GGT (rises with alcohol use; even 1–2 nights of drinking per week elevates baseline GGT over time), ALT and AST (acutely elevated after a heavy drinking session), uric acid (alcohol promotes uric acid production).

The 5-day rule: stop alcohol 5 days before your draw for the most accurate metabolic picture. If that's not realistic, a minimum of 72 hours (3 nights) is the floor — enough for acute effects to clear, though chronic markers like GGT reflect weeks to months of intake regardless.

If you've had a heavy drinking weekend closer than 5 days to your draw, let us know on your intake form. We'd rather reschedule your draw 3–5 days than have you interpret a falsely elevated triglyceride or GGT result as a chronic finding when it's acute noise.

Heavy resistance training or endurance exercise within 24–48 hours of a blood draw elevates: CK (creatine kinase) — can rise 10x above baseline after a hard leg session, persisting 72+ hours. This alone makes a CK result from a post-training draw uninterpretable. ALT — muscle damage releases ALT; a post-training ALT elevation can mimic liver pathology. Testosterone — acutely elevated immediately post-exercise (high-intensity, short rest) but drops below baseline with overtraining.

The recommendation: no high-intensity resistance training or endurance sessions 48 hours before your draw. Light walking, mobility work, and low-intensity movement are fine and won't affect results. If you train daily, substitute a light session the day before rather than zero activity — complete rest on draw day is ideal but not critical.

Maintain your usual diet during this period. Do not start a crash diet, extreme fasting protocol, or carb depletion 3 days before your draw — it distorts glucose and ketone readings. Your panel should reflect your habitual diet, not an artificial intervention.

Eat your normal evening meal. If your panel includes a fasting component (lipids, glucose, insulin), finish eating by 9–10 pm and fast through until your morning draw. A fasting window of 10–12 hours is the clinical standard; 14+ hours can paradoxically affect glucose readings in some individuals via hepatic glucose release.

Water: drink normally. Dehydration impairs venipuncture (hard to find veins), concentrates electrolytes, and can falsely elevate haemoglobin and haematocrit. At least 500 ml of water the morning of your draw before you go — more if it's a hot Bali morning. Stay off coffee for a fasting draw (coffee acutely raises cortisol and can affect glucose). Black coffee for non-fasting panels is fine.

Sleep: get a normal night's sleep. Significant sleep deprivation (< 5 hours) acutely suppresses testosterone and elevates cortisol — both real effects you don't want contaminating your baseline panel. If you've had a bad night, mention it on your intake form.

Wake up at your normal time. Drink 300–500 ml of water. For fasting panels: no food, no juice, no coffee with milk. Black coffee or plain tea is acceptable for some panels (ask Dr. Nikola if you're unsure — for lipid and glucose panels, strictly no caloric intake). Morning testosterone draws: testosterone peaks 7–10 am in men. If testosterone is in your panel, draw before 10 am for the most clinically meaningful value. Afternoon testosterone values are 15–30% lower and make comparison to reference ranges (which are typically calibrated to morning draws) less accurate.

Morning cortisol: if cortisol is in your panel, this is even more time-sensitive — draw between 7–9 am for a valid AM cortisol value. After 9 am, cortisol has dropped substantially and the result cannot be interpreted against AM reference ranges.

Take any regular medications as normal unless specifically instructed otherwise. Do not omit blood pressure medication, thyroid medication, or other daily prescriptions before a routine draw — these should be taken at your normal time. Exception: thyroid medication (T4/levothyroxine) is often drawn before the morning dose for monitoring purposes; if you're on thyroid medication, ask Dr. Nikola specifically.

Statins (e.g., rosuvastatin, atorvastatin): Continue as normal. Statins lower LDL-C — if you're testing on statins, your result reflects medicated status. Note this on your FORM intake form so Dr. Nikola can interpret accordingly and track your treated lipid profile over time.

Metformin: Continue. Metformin does not acutely affect most biomarkers on a standard panel. It does lower HbA1c and fasting glucose — again, this is what we want to track. Blood thinners (warfarin, DOACs like rivaroxaban, apixaban): Continue. These affect clotting but not most standard biomarkers. Tell the phlebotomist — they'll apply pressure longer post-draw.

Antibiotics or recent illness: Acute infection significantly elevates WBC, CRP, ESR, ferritin, and can transiently suppress testosterone. If you're in the middle of an infection or within 1 week of finishing antibiotics, consider rescheduling your draw by 2–3 weeks for the most accurate baseline. A post-illness panel is interpretable but needs context — note it on your intake form.

Post-draw: hold pressure on the site for 2 minutes. A bruise at the draw site (haematoma) is common — it resolves in 5–7 days and is cosmetic, not a complication. Eat normally after your draw if you were fasting. Avoid heavy lifting with the draw arm for 4–6 hours.

Results timeline with FORM: Dr. Nikola reviews your results within 24–48 hours of the lab releasing them. You receive a structured expert-reviewed PDF report — not just raw numbers but a contextualised breakdown of what's optimal, what to watch, and what (if anything) to act on. If a result requires urgent follow-up, Dr. Nikola contacts you directly via WhatsApp.

If a result surprises you or you want to discuss it in depth, a standalone paid 1:1 video consult with Dr. Nikola is bookable at /consult. Most clients find the expert-reviewed PDF report sufficient. For anything requiring prescriptions or further investigation, Dr. Nikola can coordinate referrals to Bali-based or home-country specialists.