It is the first time that the app's parent company Meta will proactively alert parents using Instagram's child supervision tools to searches by their child on the platform for harmful material - instead of blocking searches and directing users to external sources of help.
Parents and teenagers who are enrolled in Instagram's Teen Accounts experience, which aims to protect young users from exposure to harmful content, will be notified about the alerts from next week.
However, suicide prevention charity the Molly Rose Foundation has criticised Meta's measures and fears they "could do more harm than good".
The charity's chief executive Andy Burrows said: "This clumsy announcement is fraught with risk and we are concerned that forced disclosures could do more harm than good."
The Molly Rose Foundation was established by the family of Molly Russell - who took her own life at the age of 14 in 2017 after being exposed to self-harm and suicide content on sites such as Instagram.
Burrows explained that "every parent would want to know if their child is struggling, but these flimsy notifications will leave parents panicked and ill-prepared to have the sensitive and difficult conversations that will follow".
Meta claims that the alerts to parents about their child's searches within a short space of time on Instagram will be accompanied by expert resources to help them navigate difficult conversations with their offspring.
However, Burrows cited previous research by the Foundation which indicates that Instagram still "actively" recommends harmful content about depression, self-harm and suicide to "vulnerable young people".
He said: "The onus should be on addressing these risks rather than making yet another cynically timed announcement that passes the buck to parents."
Meta disputed the Foundation's finding when they were published last September, saying that it "misrepresents our efforts to empower parents and protect teens".
Meanwhile, the alert system will be rolled out in the UK, US, Australia and Canada at first before being deployed elsewhere across the world later in the year.
Alerts will be sent to parents via email, text, WhatsApp or on the Instagram app itself, depending on the contact information Meta has for families.
