It is possible to split the dose of Celexa in order to better tolerate the medication. Insomnia and morning fatigue may be caused by factors other than just the increase in Celexa dosage. It may be helpful to take the medication with food at dinner instead of at bedtime. If tolerance does not improve within 1-2 weeks, it is recommended to contact your doctor. It is also suggested to follow up with a pharmacist after about 5-7 days of the dosage change.