QUESTION: Is a Meyer’s cocktail safe in pregnancy and lactation?
ANSWER: First, the term Meyers / Myers is ‘fine’ if you are referring to a small volume IV push of a few vitamins and minerals as described by Gaby in Altern Med Rev 2002;7(5):389-403.
So, when I hear Myers’ I assume that is what you all mean. If you intend to describe a higher volume and content push or an IV in a bag the answer may not fit – hence my desire for specificity about what we are talking about. In some cases it could change the meaning of an answer and cause harm – so I don’t want to do that… An IV in a bag could simply be called a 250 ml Vit-Min IV formula etc.
That said, generally speaking, IV nutrients are incredibly safe in pregnancy and nursing. In most cases mom isn’t nutritionally replete anyway so both mom and baby are aided by the IV. I have studied this topic as I have done many hundreds of IV’s in pregnant and nursing women, as well as in babies and ped’s. Two main issues are considered in this population, balance of formula and potential overdose. I’ll shorten the answer to say that overdose is rare if the ordering Dr is not a complete idiot. The cases of parenterally induced damage to mom or baby are so beyond the pall of what a reasonable physician would do that in this answer they do not bear mention.
**Helpful tip: use a standard formula you know mom tolerates. Yes, in the third trimester baby increases storage of Cu and Fe, but this is by design so that baby can grow quickly after birth. (These stores are diminished or even lacking in the infant born preterm.)
**Helpful tip: if mom is replete with Fe and Cu go easy on doses but don’t short the fetus. One or two IV’s with Cu or Fe are fine even in replete moms. Balance is important for the nutrients, but again dose is everything here. If one has a low dose, low volume IV the balance of various Vitamins and minerals is less at issue (a-la a real Myers’). In a higher volume IV bag the normal balance and dosing of Vitamins or Amino Acids found in standard IV formulas is fine. Iron is given ONLY per the strict established guidelines and IMO only with additional training. Mg / K and Ca are potentially contractile so in pregnancy are dosed to tolerance. Normally I start with a Mg:Ca ratio of 1:1 to 2:1 and see how the uterus tolerates (unless in an ER treating eclampsia…). K is either omitted or a general rule of no more than 2 mEq per 250 mL of IV solution will keep you out of trouble.
Specialty IV’s are different, and given depending on clinical need and safety of additives in pregnancy or nursing. Please see the following paper for more information: