Detection of Multiple Antibiotic Residues in Turkish Pine and Blossom Honeys Using LC-MS/MS Method.

Due to the high demand for honey, beekeepers often feed the bees with antibiotics to protect honeybees against illnesses; the determination of veterinary drugs and their residues in bee products especially in honey is gaining importance. In this study, commercially available 15 different brands, a total of 22 honey (14 blossoms and 8 pines) samples obtained from 5 chain supermarkets in the city of Bingöl and Diyarbakir, Turkey were analysed for 29 antibiotic residues. These antibiotics belong to 10 different categories, including tetracyclines, aminoglycosides, macrolides, sulfonamides, fluoroquinolones, benzimidazoles, anthelmintic, amphenicols, quinolines, and oxazolidines. For the qualitative and quantitative determination of the antibiotics, a triple quadrupole liquid chromatography-tandem mass spectrometry (LC-MS/MS) was used. A total of 10 out of 22 honey (8 blossom, 57.14 % and 2 pine, 25 %) samples were found to be positive for antibiotics. Among the tested antibiotics, tetracycline, dihydrostreptomycin, streptomycin, erythromycin, and sulfadimidine were detected in the honey samples. Dihydrostreptomycin and sulfadimidine were detected in 6 samples, erythromycin was determined in 4 samples, streptomycin was found in 2 samples, and lastly, tetracycline was detected only in one sample. The highest and the lowest concentrations of antibiotics detected in the samples were dihydrostreptomycin and erythromycin found at the amount of 992.58 µg/kg and 0.77 µg/kg respectively. The proposed method was validated with a limit of quantification (LOQ) and limit of detection (LOD) ranging between 0.42 and 3.22 µg /kg and 0.13-0.97 µg /kg respectively. Good linearities were also achieved ranging between R2 =0.987 and 0.999.

Safety of IV pulse methylprednisolone therapy during breastfeeding in patients with multiple sclerosis.

BACKGROUND: Women with multiple sclerosis (MS) experience an increased risk of relapse in the postpartum period. High-dose methylprednisolone is the first-line treatment for acute relapses. OBJECTIVES: To determine the transfer of methylprednisolone into human milk in breastfeeding MS patients. METHODS: Methylprednisolone therapy was given for postpartum relapse to nine patients for three consecutive days, and seven patients received a daily infusion once a month. Breast milk samples were obtained before infusion and 1, 2, 4, 8, and 12 hours after completion of infusion. RESULTS: Methylprednisolone concentrations in milk were below detection limits immediately before infusion. Cmax was measured at 1, 2, 4, 8, and 12 hours after infusion and levels of 2.100, 1.659, 0.680, 0.174, and 0.102 µg/mL were determined, respectively. The absolute infant dose was 98.98 µg/kg/day, and the relative infant dose (RID) was 0.71% of the weight-adjusted maternal dose. CONCLUSION: The level of methylprednisolone transfer into breast milk is very low. The RID for methylprednisolone was lower than the generally accepted value. As methylprednisolone therapy is of short duration, infant exposure would be very low should a mother choose to breastfeed 1 hour after infusion. Waiting 2-4 hours after infusion will limit infant exposure still further.