An Alzheimer's patient once came to me after he had got out of his house and was found hours later in a ditch approximately 2 miles from his house.  Wandering is often a scary symptom of Alzheimer's disease and dementia.  It's confusing and scary for a senior who does not know where he/she is or where they are going; and is scary and worrisome for family caregivers.  Wandering can occur anytime but tends to increase in the late afternoon/early evening hours.  There are several things caregivers can do to keep their loved ones safe at home. 

Tip #1:  Use deadbolts on doors leading outside, place them high or low on doors
Tip #2:  Take locks off of bathroom and bedroom doors to avoid your loved one from locking themselves in
Tip #3:  As the sun starts to go down, close the blinds/curtains and turn lights on
Tip #4:  Install appliances that shut off automatically
Tip #5:  Keep toxins i.e. cleaners, bleach, poisons; and prescription medications in a safe, secure space
Tip #6:  Remove clutter from around the house
Tip #7:  Install a door alarm or place a motion sensor in your loved one's room at night to alert you when they are awake and moving
Tip #8:  Label doors, drawers, and cabinets; this is most helpful in the earlier stages

A professional geriatric care manager can help you in reviewing your home and finding assistance for home modifications.  For more tips and information, check out The Complete Guide to Alzheimer's-Proofing Your Home and home modification tips.