Research shows morphine dosage can vary greatly in newborns

Dec 22 2009

Dosage recommendations for newborns being cared for in an intensive care unit will in the future most likely be based on more individual characteristics than just body weight. This is the result of a study conducted by the Dutch Top Institute Pharma in which Leiden University (Prof M. Danhof) and the Rotterdam Erasmus Medical Centre/Sophia Children's Hospital (Prof D. Tibboel) are represented.

Catherijne Knibbe, clinical pharmacologist from the Leiden/Amsterdam Centre for Drug Research of Leiden University: "For morphine the preliminary study results show that for example a quarter of the current standard dose is sufficient for premature babies. The Erasmus MC/Sophia Children's Hospital had already noted in practice that some babies experienced withdrawal symptoms after long-term treatment with morphine. Now research has shown that the required amount of morphine can vary greatly per baby."

The dosage for children is often adjusted solely according to body weight, but that now seems to be insufficient. Knibbe said about the common used sedative midazolam: "A healthy child may be prescribed far more midazolam than for example a child with the same body weight lying in the intensive care unit with a severe infection. This study provides guidelines for arriving at a dosage recommendation that is adjusted better to the individual child. This is an enormous advance." According to Knibbe, this information is very important for doctors, as well as for pharmaceutical companies, which have been required for the past two years to conform to stricter European legislation for medicinal products for children.

This study required an intensive collaboration between clinical pharmacologists and pediatricians from the various institutes using modern methods like PK/PD modeling. Complex computer models can determine the correct dosage from small quantities of blood, taking into account the child's specific characteristics. Knibbe: "We know too little about the effects of medicinal products on children, especially newborns. Although we actually need more information than for adults. Children change so rapidly. In the first year of life the child changes each week, and responds differently and breaks down medicinal products differently. I think that these study results will mean that in some cases children will receive less medication, and thus fewer adverse effects will develop, while the child will still be treated well. I consider that a major benefit: for doctors, but most especially for the children and their parents."

SOURCE Top Institute Pharma