Thank you for the question posted, According to your daughter’s chief complaint, it seems she is suffering from a chronic psychological disorder known as ADHD (Attention Deficit Hyperactivity Disorder). You have mentioned that she is now pregnant and stopped her treatment for ADHD while suffering from withdrawal syndromes such as emotional stress, etc. To understand the effect of medication therapy during pregnancy, you can consider on the USA- FDA (Food Drugs Administration) classification. Class A shows safe drugs such as Levothyroxine, folic acid, class B shows probably okay and safe in human fetus such as Metformin and Amoxicillin. Class C shows harmful in animal studies but convincing evidence is not available in human demonstrating harmful effect on fetus such as Gabapentin. Class D shows a harmful effect in fetus such as Alprazolam and Losartan. Class X shows very harmful effect on fetus such as Atorvastatin and Warfarin. To answer your previous question, please notice that Adderall medication is a combination drug containing salts of amphetamine. Additionally, Amphetamine is classified as class C by the USA – FDA showing that yet there is not convincing evidence available showing that this drug makes harms in fetus. Please consider that valium (Diazepam) is classified as category D showing that maybe harmful effect on fetus. To avoid imposing any harmful effet on the fetus and mother, a risk-benefit analysis has to be performed by your daughter’s gynecologist for appropriate medication therapy demanded. You may consult jointly with a psychologist either. Any substitution therapy has to be confirmed jointly by gynecologist and psychologist. In conclusion, I refuse diazepam substitution in your case. Hope you find my recommendation helpful, Regards