Intended for healthcare professionals

Rapid response to:


Adverse drug reactions to tocolytic treatment for preterm labour: prospective cohort study

BMJ 2009; 338 doi: (Published 06 March 2009) Cite this as: BMJ 2009;338:b744

Rapid Response:

Nifedipine adverse reactions exaggerated

So ritodrine use in preterm labour produces a lot more adverse
reactions to mother and fetus than atosiban or nifedipine.

All 3 are equally effective.

Nifedipine reduces uterine contractions, as does atosiban.

Nifedipine presents a more favorable safety profile for the fetus,
compared to atosiban.

But atosiban presents a more favorable safety profile for the mother,
compared to nifedipine, this study concludes.

I believe that this last conclusion is biased, because the only
serious adverse reaction of nifedipine observed, hypotension, could have
been completely absent!

Administering nifedipine sublingually, every 15 minutes, or per os,
every 4 hours, is known to cause hypotension.

That is why 60mg controlled release tablets of nifedipine have been
produced and exist on the market!

If this formulation had been used during this, and other, studies,
the adverse reactions of the nifedipine group of patients would be
similar, or fewer, compared to those of the atosiban group of patients.

Future studies should only compare 60mg controlled release tablets of
nifedipine to i.v. atosiban.

All other aspects favor nifedipine use (cost, route of
administration, effects on fetuses).

If future studies compare mother safety profiles of atosiban and
nifedipine and find them similar, then only nifedipine should be
recommended for the management of preterm labour.

Competing interests: No competing interests

11 May 2011
Stavros Saripanidis
Consultant in Obstetrics and Gyneacology in Greece
Private Sector, 55131