Plaquenil® (Hydroxychloroquine sulfate) – Risk of major congenital malformations and new risks of phospholipidosis and aggravation of myasthenia gravis symptoms

A Dear Healthcare Professional Letter has been issued by Sanofi-Aventis Pte Ltd to inform healthcare professionals that the Huybrechts study published in 2021 suggested a small increase in the relative risk of major congenital malformations associated with the use of hydroxychloroquine in the first trimester of pregnancy, especially when used at a high daily dosage (≥ 400mg daily). Healthcare professionals are advised to avoid prescribing daily doses of ≥ 400mg in the first trimester of pregnancy except when, in the judgement of the healthcare professional, the individual’s benefits outweigh the risks. It is also advisable to closely monitor the pregnancy, especially during the first trimester, for early detection of major congenital malformations. If there is no alternative treatment to hydroxychloroquine, the lowest effective dose should be used. In addition, new risks of phospholipidosis and aggravation of myasthenia gravis symptoms have been reported with the use of hydroxychloroquine. Healthcare professionals are advised to discontinue hydroxychloroquine in patients if cardiac, renal, muscular or nerve toxicity is suspected or if aggravation of myasthenia gravis symptoms is suspected. The local package insert of Plaquenil^® is being updated to include these information. Please refer to the letter for details.

Published: 19 Sep 2024

Dear Healthcare Professional Letters