Toxnet, the database of substance toxicity says, Precautions: Because of lack of long-term safety studies, ALC is not advised for pregnant women or nursing mothers
That's good news
Researchers determine the specific conditions of each experiment, including peptide concentrations, exposure times, and study protocols, based on their research goals and institutional guidelines
In fact, some older animal studies show that L-citrulline may be more effective at increasing arginine levels than L-arginine supplements
doi: 10.1038/s41421-024-00750-4 181 ZhuJWangHLiuYLiWCaoLWangWet al
Countries are Belgium, Canada, China, Denmark, Germany, India, Ireland, Italy, Portugal, Sweden, Switzerland and Taiwan