Zuclopenthixol levels in serum and breast milk

Breast milk and serum samples were obtained from six psychotic patients 3 days–10 months after delivery. Five of the women were given zuclopenthixol PO daily, and one was given zuclopenthixol decanoate IM every 2 weeks. Zuclopenthixol was estimated in breast milk and serum by high performance liquid chromotography. The zuclopenthixol levels in milk were found to be 29% of the serum levels on average. Based on the drug levels found in milk, the daily dose to a suckling infant was estimated to be 0.5–5 g zuclopenthixol, corresponding to a dose of 0.01–0.1 mg to an adult. It is not likely that such a low dose would cause any effects or side effects in the infant unless infants are very different from adults concerning metabolism or sensitivity to the drug. The suckling infants included in this study were apparently not influenced by the intake of zuclopenthixol with the milk.     

Factors affecting levels of DDT and metabolites in human breast milk from Kwazulu

Concentrations of p,p'-DDT, p,p'-DDE, and p,p'-DDD have been determined in breast milk of mothers residing in two different areas of KwaZulu. Annual intradomiciliary application of DDT was used for the interruption of malaria transmission in one area, while the other served as the control. Milk from mothers living in DDT-treated dwellings had significantly higher mean levels of DDT and metabolites (mean sigma DDT 15.83 mg kg-1 in milk fat) than those from the control area (0.69 mg kg-1). The highest recorded sigma DDT value was 59.3 mg kg-1 (milk fat). Primiparous mothers from the malarious area had significantly more sigma DDT and metabolites (sigma DDT 24.82 mg kg-1) than multiparous mothers from the same area (mean 12.21 mg kg-1). Parity was the best predictor of DDT in breast milk of the exposed group. The percentage DDT and the sigma DDT increased significantly with an increase in parity. The same, but not significant, trend was also found for the control group. It was hypothesized that the increase in percentage DDT that occurred with higher parities was due to the uptake of DDT and elimination via milk. This process was faster than the uptake and endogenous formation of DDE. Designing predictive models using multiple regression was not very successful. The recorded levels do not represent an appreciable health risk to the mothers. From the literature it was deduced that at the recorded levels, a well-founded risk to the infants, particularly the firstborns, exists in sprayed areas.     

Lidocaine excretion in breast milk

Nursing mothers are occasionally treated with intravenous lidocaine for ventricular dysrhythmias. There have been no reports on the excretion of lidocaine into breast milk. This case documents the excretion of lidocaine into breast milk in small amounts and shows the validity of the TDx methodology used in the whole-milk lidocaine assay. We observed breast-milk concentrations of lidocaine at 40 percent of the serum levels. Clinical practitioners should be aware the lidocaine is excreted into breast milk in small amounts and the mother could probably continue to safely breast-feed her child while on parenteral lidocaine. Any adverse reactions in the nursing infant would probably be limited to an idiosyncratic or allergic reaction.     

Piroxicam in human breast milk

Summary In 2 nursing women, piroxicam was present in breast milk at about 1% of the concentration in maternal serum. None was detected in serum from the baby fed by one of them.     

Amphetamine secretion in breast milk

Summary The excretion of amphetamine in human breast milk was studied in a nursing mother with narcolepsy, who was treated with 20 mg daily of a racemic preparation of amphetamine. The concentration of amphetamine was 3 and 7 times higher in breast milk than in maternal plasma on the 10th and 42nd days after delivery. Small amounts of amphetamine were found in urine samples from the infant.     

Zolpidem excretion in breast milk

Five, lactating, healthy white women were treated with a single 20 mg tablet of zolpidem 3-4 days after the delivery of a full term baby. The drug was administered at 20.00 h, 30 min after dinner, and milk samples were collected before and 3, 13 and 16 h. Venous blood 5 ml was taken before and 1.5, 3, 13, 16 h after zolpidem administration. The apparent elimination half life, estimated from plasma zolpidem concentrations was 2.6 h. The amount of zolpidem excreted in the milk at 3 h ranged between 0.76 and 3.88 micrograms, which represented 0.004 to 0.019% of the administered dose; no detectable (below 0.5 ng/ml) zolpidem was found in the milk at subsequent sampling times. The ratio of the zolpidem concentrations in breast milk and plasma at 3 h was 0.13. The apparent breast milk clearance of zolpidem, calculated from the ratio of the total amount of zolpidem excreted in milk to its AUC in plasma was 1.48 ml/h. The results show that the excretion of zolpidem in human milk is very low (below 0.02%) and that most of it takes place during the first 3 h following drug intake.     

Hydroxychloroquine in human breast milk

Summary Hydroxychloroquine 3.2 µg was detected in breast milk from a woman given 800 mg over 48 hour.     

Methylxanthine levels in breast milk of lactating women of different ethnic and socioeconomic classes.

The purpose of this study was to evaluate the dietary caffeine and dimethylxanthine concentrations in breast milk of 40 mothers from different ethnic and socioeconomic backgrounds. Their diets and drug intake were not restricted in any way. Each nursing mother provided a fasting and a combined breast-milk sample each day for 3 consecutive days. No significant differences were found in intake levels of any of the methylxanthines among the groups tested. No significant differences were found among the four groups in breast-milk levels of caffeine, theobromine, or paraxanthine. However, the mean theophylline milk levels were significantly higher on 2 of the 3 days examined in Anglo-American woman compared to Hispanic-American women. Socioeconomic and ethnic variables were also compared among the four groups. The daily amounts of methylxanthines found in the breast milk of this free-living population of mothers do not appear to present clinically significant amounts to the infant.     

Excretion of citalopram in breast milk

Aims The objective of this study was to measure the secretion of the selective serotonin uptake inhibitor citalopram in breast milk.
Methods The excretion of citalopram in breast milk was studied at steady-state conditions in two patients with depression and in one healthy volunteer after ingestion of a single dose citalopram.
Results Milk/serum concentration ratios based on single pairs of samples from the two patients ranged from 1.16 to 1.88. Based on milk concentration data from the patients, the absolute dose ingested by a suckling infant would be 4.3–17.6  μg  kg⁻¹ day⁻¹, and the relative dose 0.7–5.9% of the weight-adjusted maternal dose. Based on area-under-the-time-concentration curves from the healthy volunteer, the milk/serum ratio was 1.00, the absolute dose to the infant during steady-state conditions would be 11.2  μg  kg⁻¹ day⁻¹ and the relative dose 1.8% of the weight-adjusted maternal dose.
Conclusion The study shows that the relative dose to a suckling infant is close to that reported for fluoxetine, and higher than reported for fluvoxamine, paroxetine and sertraline.     

Excretion of oxazepam in breast milk

Summary Oxazepam was measured in plasma and breast milk during 3 days of medication and 10 and 34 h after the last dose. The half-life estimated from levels in plasma and milk was approximately 12 hours. Less than 1/1000 of the maternal dose would have been excreted in 11 breast milk.