Brief Answer:
Magnesium doesn't cause insomnia.

Detailed Answer:
Hello,
Milk of magnesia and magnesium supplements do not cause insomnia. Indeed, they are used to treat insomnia. Among the medications you take only trazodone can cause insomnia that too in very rare <1% of cases.
So your insomnia may not be related to drug intake.various causes of insomnia are :
1)Life stressors including your job, relationships, financial difficulties and more.
2)Unhealthy lifestyle and sleep habits.
3)Anxiety disorders, depression and/or other mental health problems.
4)Chronic diseases like cancer.
5)Chronic pain due to arthritis, fibromyalgia or other conditions.
6)Gastrointestinal disorders, such as heartburn.
7) few medications and substances.
Treatment can include the following:
1)Avoid large meals, caffeine and alcohol before bed.
2)Be physically active during the day, outside if possible.
3)Cut back on caffeine, including coffee, sodas and chocolate, throughout the day and especially at night.
4)Go to bed and get up at the same time each day, including weekends.
5)Put away smartphones, TVs, laptops or other screens at least 30 minutes before bedtime.
6)Quit smoking.
7)Turn your bedroom into a dark, quiet, cool sanctuary.
8)Unwind with soothing music, a good book or meditation.
9) medications like zolpidem 10 mg can be used at bed time for sleep onset.
If all the above measures fail, you may need a benzodiazepine like lorazepam and cognitive behavioural therapy.
Hope i have answered your question. Please let me know if you need any further assistance. Thank you.
Take care.

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