Q. My child is having neutropenia after taking Paracetamol and Ibuprofen. Why?

Hello doctor,

My 10-month-old baby had a viral infection with roseola infantum. It started with fever of 101.3 degrees Fahrenheit and 102.2 degrees Fahrenheit measured rectally on the second day treated with Ibuprofen 3.5 ml and Paracetamol (Panadol) 4 ml administrated after 6 hours (almost three days of treatment). The third day, the baby did not have fever at all and on the fourth day a rash appeared on his face, after his ears and on his back mainly, with mild signs on his tummy. Also, in the fourth day she had changes in his stool- kind of yellow with mucus and quite fluid with no fever.

Five days later, the blood tests indicated severe neutropenia with 0 neutrophils on a test taken from her finger. As we got very scared, we repeated the test the next day and the result was 0.2 neutrophils so again a very low value.

My question is that is it possible that this neutropenia is a consequence of the roseola infantum plus the administration of Paracetamol? The baby is fine now, she is very happy, playing, and eating normal. Also, would it be possible that these indicators can be so low due to the way of taking blood sample? We got it out of her finger, not through the veins. We were given Azithromycin just to be on the safe side, but I would not give her antibiotics if clinically she is well and shows no sign of being unwell.