How long does it typically take for Namenda to work its way completely out of your system after?

Jgreg1957, welcome to the site. I do hope by now our mother is doing better. New studies have showed that Nemda does not help in conjuction with Aricept for helping cognitive behaviors. As far as how long it takes to leave your system read the following or check with her pharmacist if you do not understandd this:

Half-life

Terminal half-life is approximately 60–80 hours.1

Special Populations

In patients with hepatic impairment, only a modest effect on clearance is expected.1

Renal impairment increases exposure.1 AUC increased by 4, 60, or 115% in individuals with mild (Clcr >50 but <80 mL/minute), moderate (Clcr 30–49 mL/minute), or severe (Clcr 5–29 mL/minute) renal impairment, respectively.1 Terminal elimination half-life increased by 18, 41, or 95% in those with mild, moderate, or severe renal impairment, respectively.1 (See Renal Impairment under Dosage and Administration and under Cautions.)

In geriatric patients, pharmacokinetics similar to those in younger adults.

Wishing you both the best...