Brief Answer:
Clonazepam or lorazepam is the option

Detailed Answer:
Hello,

Thanks for writing to us.

Among seroquel, trazodone and ambien; ambien is the only medicines specifically used for sleep disturbance. Other two have sedation as a side effect and helpful in sleep problem.

Ambien is useful for sleep induction means it helps to fall in sleep fast. it can not maintain sleep for long.

Lorazepam(ativan) or Clonazepam(klonopin) can be used specifically for sleep problem in your case. They are not going to affect your SIADH condition.They can help in sleep induction as well as sleep maintenance.

No sleeping pills should be taken without consulting doctor and written prescription.

Please consult your treating doctor for above medicines,let doctor decide the dose and write prescription.

Note:Insomnia are of two types.
Primary insomnia: Only sleep disturbance is the problem. No other physical or psychological disturbance. In this type sleeping pills as well as some measures called Sleep Hygiene are useful.
Secondary Insomnia: In this insomnia is secondary to some physical or psychological problem is present. Sleeping pills and Sleep Hygiene are useful but main stay of the treatment is to treat underlying physical or psychological condition.

Hope I have answered your query, I will be happy to help further.

Regards,
Dr.Chintan Solanki.

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