The Usefulness of Saliva in Therapeutic Drug Monitoring of Caffeine in Preterm Infants.

Abstract

Aim To verify if the concentrations of caffeine in saliva are comparable to the serum concentrations in preterm infants treated with caffeine for apnoea of prematurity. Methods Prospective observational study. Eligible patients were newborn infants < 37 weeks of gestational age treated with oral or intravenous caffeine for apnoea of prematurity. Two paired samples of saliva-blood were collected per patient. Tube solid phase microextraction coupled on-line to capillary liquid chromatography with diode array detection were used for analysis. Results A total of 47 newborns with a median gestational age 28 [26–30] weeks and mean of 1.11 ± 0.4 kg of birth weight. Median postmenstrual age, when samples were collected, was 31 [29–33] weeks. Serum caffeine median levels of 19.30 µg/mL [1.9–53.90]and salivary caffeine median levels of 16.36 µg/mL [2.20–56.90] were obtained. There was a strong positive Pearson’s correlation between the two variables r = 0.83 (p < 0.001). Conclusion The measurement of caffeine salivary concentrations after intravenous or oral administration offers an alternative to serum caffeine monitoring in apnoea of prematurity.

Salivary Therapeutic Monitoring of Buprenorphine in Neonates After Maternal Sublingual Dosing Guided by Physiologically Based Pharmacokinetic Modeling

“…27,28 This is especially valid for medications with significant plasma–saliva drug concentration correlations. 29,30 Although both BUP and NorBUP have quantifiable concentrations in the saliva of adult and pregnant populations, 33,34 the salivary BUP levels were almost 80-fold those of NorBUP. 33 Thus, the salivary TDM of BUP is more suitable than NorBUP's.…”

“…27 The noninvasive convenient salivary TDM in infants avoids these issues 28 and has been applied to many medications. 29,30 In addition, salivary concentrations of drugs are comparable with free drug levels in plasma. 31,32 BUP and NorBUP showed measurable levels in the saliva of pregnant and adult populations.…”