A woman, now pregnant in week 7, has during the first 6 weeks of the pregnancy taken Malarone (atov

Fråga: A woman, now pregnant in week 7, has during the first 6 weeks of the pregnancy taken Malarone (atovaquone + proguanil) because of a travel to Africa. Are there risks for fetal damage?

Sammanfattning: Proguanil taken as malaria prophylaxis during pregnancy has been widely used for several decades and is considered to be safe. In contrast, no documentation concerning neither risks nor safety of atovaquone in pregnancy has been found in the literature. Therefore, atovaquone should be used in pregnancy only after special consideration. The exposure to the compound during early pregnancy cannot, however, be considered as an indication for abortion. The case should be followed up and the outcome of the pregnancy reported.

Svar: The use of proguanil as malariaprophylaxis during pregnancy has been discussed previously in several Drugline documents (1,2,3). In summary, there is no documentation or suspicion that malaria prophylaxis with proguanil would be associated with any increased risk of fetal damage.

In contrast, no information concerning the use of atovaquone during pregnancy has been found in the literature. In animal studies, the use of atovaquone in rabbit has been associated with an increased frequency of resorption and decreased length and weight of the fetus (4). It is unclear whether these effects are secondary to the toxicity that is observed in the mother animal. Due to the limited experience of atovaquone during pregnancy, the drug should only been given to pregnant women after special consideration (4).

Neither the manufacturer (5) nor professor Bengt Källen (6) has knowledge of any reports on the outcome of pregnancy in women treated with Malarone. Neither has any negative outcome of pregnancy after exposure to atovaquone been reported to the Swedish Adverse Drug Reaction Advisory Committee or the WHO side effect register. It is recommended that the present exposure to Malarone is reported on the enclosed form to the manufacturer.