Volume 182 - Issue 12
Life-threatening milk-alkali syndrome resulting from antacid ingestion during pregnancy
Author: Adam P Morton
Med J Aust 2005; 182 (12): 654-655. || doi: 10.5694/j.1326-5377.2005.tb06865.x
Published online: 20 June 2005
Published online: 20 June 2005
To the Editor: I read with interest the Lessons from Practice article on milk-alkali syndrome during pregnancy.1 I would like to offer the following comments.
The patient’s alkalosis was in fact more impressive than presented, as the authors used the reference range for serum bicarbonate in non-pregnant patients. During pregnancy, serum bicarbonate levels typically fall by about 4 mmol/L to compensate for the respiratory alkalosis caused by elevated progesterone levels stimulating respiratory drive.
Given the patient’s life-threatening calcium level on presentation, I am interested to know whether calcitonin treatment or even dialysis was considered while waiting for the pamidronate to take effect.
An important aspect that the authors did not discuss in relation to this case is the reassuring data on the safety of both proton-pump inhibitors and H2-receptor antagonists in pregnancy. While there is more experience with the latter, two recent studies found no evidence of teratogenicity in almost 900 cases of exposure to proton-pump inhibitors in the first trimester.2,3 Clinicians should feel comfortable about prescribing these medications in pregnancy.
After reporting a similar case,4 I wrote to Walco, the manufacturers of Quick-Eze, who subsequently changed their product labelling to include a warning about the number of tablets that could be safely taken each day. Disappointingly, they did not include a warning about ingestion during pregnancy, as I suggested.
References
- Gordon MV, McMahon LP, Hamblin PS. Life-threatening milk-alkali syndrome resulting from antacid ingestion during pregnancy. Med J Aust 2005; 182: 350-351.
- Diav-Citrin O, Arnon J, Shechtman S, et al. The safety of proton pump inhibitors in pregnancy: a multicentre prospective controlled study. Aliment Pharmacol Ther 2005; 21: 269-275. i1085774
- Nikfar S, Abdollahi M, Moretti ME, et al. Use of proton pump inhibitors during pregnancy and rates of major malformations: a meta-analysis. Dig Dis Sci 2002; 47: 1526-1529. i1085776
- Morton A. Milk-alkali syndrome in pregnancy, associated with elevated levels of parathyroid hormone-related protein. Intern Med J 2002; 32: 492-493. BABDEAAA