No I didn't see the sources. But this is what AI from Mayo says.

Mayo Clinic recommends consulting a doctor before using Milk of Magnesia, especially if you have kidney issues, are pregnant, or are taking other medications, as it can interact with them. As a saline laxative, it works by drawing water into the intestines to soften stool and promote bowel movements, and it's a short-term solution for occasional constipation. You should not exceed the recommended dosage and should see a doctor if constipation lasts more than seven days or if you experience severe side effects like persistent cramps or severe diarrhea.

When to Use With Caution

Pregnancy and Kidney Problems:
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Always consult a doctor before taking Milk of Magnesia if you are pregnant or have kidney disease.
Medication Interactions:
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It can reduce the absorption of other medications, so it is crucial to check with a doctor or pharmacist before use if you are taking other medicines.
Underlying Conditions:
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If you find yourself needing Milk of Magnesia often or if your constipation persists, it could signal an underlying medical condition that requires a doctor's attention.

When to See a Doctor
Contact a healthcare professional immediately if you experience:

Severe or persistent stomach cramps or pain
Severe, prolonged, or unexplained diarrhea
Bloody stools or rectal bleeding
Dizziness, lightheadedness, or unusual tiredness
Constipation that lasts for more than seven days