Hydroxyurea lay dormant for more than fifty years until it was studied as part of an investigation into the toxicity of protein metabolites. Due to its chemical properties hydroxyurea was explored as an antisickling agent in the treatment of hematological conditions. One common mechanism for synthesizing hydroxyurea is by the reaction of calcium cyanate with hydroxylamine nitrate in absolute ethanol and by the reaction of salt (i.e. sodium or potassium) cyanates and hydroxylamine hydrochloride in aqueous solution. Hydroxyurea has also been prepared by converting a quaternary ammonium anion exchange resin from the chloride form to the cyanate form with sodium cyanate and reacting the resin in the cyanate form with hydroxylamine hydrochloride. This method of hydroxyurea synthesis was patented by Hussain et al. (2015). Pharmacology
Hydroxyurea is a monohydroxyl-substituted urea (hydroxycarbamate) antimetabolite. Similar to other antimetabolite anti-cancer drugs, it acts by disrupting the DNA replication process of dividing cancer cells in the body. Hydroxyurea selectively inhibits ribonucleoside diphosphate reductase, an enzyme required to convert ribonucleoside diphosphates into deoxyribonucleoside diphosphates, thereby preventing cells from leaving the G1/S phase of the cell cycle. This agent also exhibits radiosensitizing activity by maintaining cells in the radiation-sensitive G1 phase and interfering with DNA repair.Biochemical research has explored its role as a DNA replication inhibitor which causes deoxyribonucleotide depletion and results in DNA double strand breaks near replication forks (see DNA repair).
Neonatal hypoglycemia occurs when the neonates blood glucose level is less than the newborns body requirements for factors such as cellular energy and metabolism. There is inconsistency internationally for diagnostic thresholds. In the US, hypoglycemia is when the blood glucose level is below 30 mg/dL within the first 24 hours of life and below 45 mg/dL thereafter. In the UK, however, lower and more variable thresholds are used (<18 mg/dL at any time OR baby with abnormal clinical signs and a single value <45 mg/dL OR baby at risk of impaired metabolic adaptation but without abnormal clinical signs and a measurement <36 mg/dL and remaining <36 mg/dL at next measurement). The neonates gestational age, birth weight, metabolic needs, and wellness state of the newborn has a substantial impact on the neonates blood glucose level. There are known risk factors that can be both maternal and neonatal. This is a treatable condition. Its treatment depends on the cause of the hypoglycemia. Though it is treatable, it can be fatal if gone undetected. Hypoglycemia is the most common metabolic problem in newborns.Neonatal hypoglycemia occurs in between 1 in 3 births out of every 1,000 births but is hard to quantify internationally due to lack of consensus about diagnostic thresholds. It often occurs in premature babies, small full-term babies, babies of diabetic mothers, and is more common in neonatal hypoxic asphyxia, sclerosis, and infected sepsis. Severe hypoglycaemia with persistent or repeated episodes can cause damage to the central nervous system.