Kommersiellt obunden läkemedelsinformation riktad till läkare och sjukvårdspersonal

Drugline nr 22344

Publicerat 2005-09-23


Is praziquantel (Cesol, Biltricide) compatible with breast-feeding?

A woman who has recently delivered a healthy child has been diagnosed with beef tapeworm (Taenia saginata) infestation. The questioner wants to know whether praziquantel therapy is compatible with breast-feeding.


Praziquantel is an anthelminthic normally used as a single dose 40-75 mg/kg. The documentation on praziquantel during human pregnancy and lactation is scant. The available documentation is mainly for treatment of bilharzia, that is a more severe infection for both the mother and the child, than is tapeworm infestation (1).

It passes over to breast milk and milk concentrations up to one quarter of the mother´s plasma concentration have been measured (1). The oral absorption is rapid and relatively complete, but first-pass metabolism is extensive (2). The estimated relative infant dose is 0.01% (3). We have found no published data on the bioavailability of praziquantel, but from data in (4) the systemic availability of unchanged drug can be calculated to be no more than 1%. Due to immaturity, the bioavailability in the infant may be higher.

The plasma half-life of praziquantel is approximately 1.5 hours. In a study with C14-praziquantel the overall half-life was calculated to be about 4 hours and 80-85% of a given dose was eliminated renally within four days. However, 90% of this elimination occurred within 24 hours (4). The manufacturer recommends breast-feeding to be postponed to 72 hours post-dose (1). The major metabolite has some pharmacological activity (2).

The adverse events that have been observed are mainly due to lysis of parasites (2). Thus in a lactating child, which would not be infested itself, no adverse events would be expected. When treating bilharzia the risks of not treating the mother is considered to outweigh the potential risks to the nursing child, even when bottle-feeding for 48-72 hours is not applicable, which may be the case in developing countries (5). Tapeworm infestation is in most cases not life-threatening to the mother and the benefit to the child of treatment during lactation is none unless the infestation leads to severe malnutrition and premature weaning. Thus, treatment can often wait until the child is weaned off.

If treatment during lactation is considered necessary, the suggested 72 hours seems very conservative considering the short half-life and rapid elimination. Therefore, we suggest that lactation is withheld for 24 hours.


There is seldom a need to treat tapeworm infestation during lactation. When so is the case, however, due to infinitesimal infant dose, rapid elimination, and lack of serious toxicity treatment could be commenced, but discarding of the breast milk is recommended for 24 hours as a measure of safety.

Hellden A
Ohlsson S


  1. Briggs GG, Freeman RK, Yaffe SJ. Drugs in pregnancy and lactation. 7th ed. Philadelphia: Lippincott Williams & Wilkins; 2005.
  2. Dollery C Sir, editor. Therapeutic drugs. 2nd ed. Edinburgh: Churchill Livingstone; 1999.
  3. Drugline no 17345 (year 2000).
  4. Patzschke K, Putter J, Wegner LA, Horster FA, Diekmann HW. Serum concentrations and renal excretion in humans after oral administration of praziquantel - results of three determination methods. Eur J Drug Metab Pharmacokinet 1979;4(3):149-56.
  5. Olds GR. Administration of praziquantel to pregnant and lactating women. Acta Trop 2003;86:195-95.

Senast ändrad 2018-09-20