Believe it or not Unisom should not be used for morning sickness and it shouldn't be use by pregnant women. It's used as a sleep-aid, but it does contain an antihistamine.
Talk to your doctor or pharmacist, we'll be more than happy to help you, one of their options could be a Sea-Band which is a wrist bracelet that pregnant women can wear. It applies pressure around their wrist and helps with morning sickness.
Also changes to your diet, eating smaller meals, things like saltine crackers and items like that have really shown to be beneficial.
There are really no prescription medications that are available for morning sickness unfortunately, but by talking to your doctor or pharmacist will be able to make sure you make the right choice of this.
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