What is the recommended lancet length for adults?

• A. 1-2 mm
• B. 2-4 mm
• C. 3-5 mm
• D. 4-6 mm

Answer: (B)

The key idea is to choose a puncture depth that reaches the capillary bed in the fingertip without going too deep into tissue. In adults, the skin and underlying tissues are thicker, so a depth that’s too shallow may not yield enough blood, while a depth that’s too deep increases pain and the risk of hitting deeper structures. A lancet in the 2–4 mm range reliably reaches the capillaries in the fingertip pulp, giving an adequate blood sample with minimal discomfort. Going deeper than this raises the chance of more pain and potential tissue injury, while shallower depths may fail to produce sufficient blood. So, 2–4 mm is the best-balanced choice for adults.