Zinc (Zn) challenge Test (1.5 hours)


There are c.200 mammalian enzymes that require zinc as a co-factor and hence its deficiency has a multiplicity of effects in humans.

Take a fasting blood sample. Blue top (trace- element free).

Give 220mg of Zn So4. 7 H2O in 75 ml of water (equivalent to 50 mg of zinc). Dilution of the zinc is required so that it does not act as an irritant to the stomach.

Take a second blood sample 90 minutes later and measure theplasma zinc concentration in both samples.

The serum zinc in the 90 minute sample should be approximately 3 x the fasting zinc value; if not , this is evidence of zinc malabsorption.

Patient Instructions:

Patient should fast for at least 8 hours.

Sample Requirements:

2 x Navy Blue (EDTA) - Fasting and 90 minutes

Postal Samples Acceptable:


For further details please contact the laboratory at: lab@xxxxbiolab.co.uk