TOKYO - A shortage of penicillin, the first-choice treatment for syphilis, continues in Japan amid persistently high infection levels, with production, halted due to an equipment failure at a manufacturer's plant, not expected to resume until late next year.
The drug is also the only one recommended for preventing mother-to-child transmissions, prompting the Japanese Society for Sexually Transmitted Infections to ask medical professionals to prioritize its use for pregnant women.
Syphilis, a sexually transmitted infection, has been increasingly reported since around the end of the coronavirus pandemic, with cases rising from about 6,000 in 2020 to more than 13,000 in 2025.
If transmitted to a fetus through the placenta, it can lead to stillbirths or premature births, as well as congenital syphilis, which can cause neurological and bone abnormalities in children.
Against this backdrop, Pfizer Inc.'s syphilis treatment was voluntarily recalled in July 2025 because of contamination by foreign matter, with a manufacturing equipment failure occurring in November that year.
The company said it expects shipments to resume around the "latter half of next year," citing the time needed to prepare facilities and undergo regulatory checks.
The Japanese organization issued guidance for medical institutions on Aug. 24, urging them to avoid unnecessary prescriptions after assessing patients' conditions and asking pharmacies not to place large orders due to supply concerns.
It also proposed prioritizing pregnant women and patients for whom alternative drugs are not suitable.
Hiroshige Mikamo, a professor at Asahi University in Gifu Prefecture, described the move as "a preventive step to protect patients' treatment opportunities."
The professor, who chairs the organization's syphilis committee, also advised patients to continue to seek medical care despite the shortage.
