Question 1 Alzheimers disease (AD)s root cause is still unclear and scientists believe the disease can be multifactional including neuron degeneration, reduction of cholinergic transmission, the formation of ?-Amyloid and neuritic plaques, neurofibrillary tangles and tau, apolipoprotein E4, the endoplasmic, the reticulum-associated binding protein (ERAB), and homocysteine (Rosenthal & Burchum, 2019). For dementia treatment, the two approved drug classes commonly used are Cholinesterase inhibitors and N-Methyl-D-Aspartate Receptor Antagonist (NMDA) (Rosenthal & Burchum, 2019).Patients suffering from dementia may experience neuropsychiatric symptoms (NPS) including mood disorders, sleep disorders, psychotic symptoms, and agitation (Aigbogun, Stellhorn, Hartry, Baker, & Fillit, 2019). Among the discussed NPS, common behavioral disturbances experienced by AD patients are depression and hallucinations which can significantly decrease the patient and familys quality of life (Rosenthal & Burchum, 2019). The article by Rosenthal and Burchum highlights that antidepressants and antipsychotic agents are used widely to help patients control NPS effectively (2019). Levodopa is the dopamine precursor that is recommended for patients with Parkinsons disease who have progressive symptoms and cannot be controlled with anti-parkinsonism drugs (Gandhi & Saadabadi., 2023). Levodopa is studied to cross the blood-brain barrier and turn to dopamine in the central nervous and peripheral nervous systems; as a result, the level of dopamine can prevent the disruption of the nigrostriatal pathway (Gandhi & Saadabadi., 2023). Common side effects of levodopa are nausea, dizziness, headache, and somnolence (Gandhi & Saadabadi., 2023). In older populations, taking levodopa can lead to confusion, hallucinations, delusions, psychosis, and agitation. (Gandhi & Saadabadi., 2023). The healthcare providers should educate the patient should not stop or reduce the medication to prevent withdrawal symptoms (Gandhi & Saadabadi., 2023).According to the article by Gandhi and Saadabadi, Levodopa is usually administered with peripheral decarboxylase inhibitors such as carbidopa and benserazide in order to enhance the bioavailability and decrease Levodopa adverse effects (2023). Since carbidopa is proven to prevent levodopa from converting to dopamine outside the CNS, the medication when used together with levodopa can inhibit unexpected side effects of levodopa in the PNS (Gandhi & Saadabadi., 2023).According to Rosenthal and Burchum, PD can be treated with Monoamine oxidase B (MAO-B) inhibitors (for mild symptoms of PD), catechol-O-methyltransferase inhibitors (COMT), carbidopa-levodopa, or dopamine agonists (DA) (2019). Some common drugs are rasagiline (MAO-B), entacapone (COMT), ropinirole (DA), pramipexole (DA) (Rosenthal & Burchum, 2019).Venlafaxine is the serotonin-norepinephrine reuptake inhibitor (SNRI) medication that works at the presynaptic terminal in the brain to prevent the reuptake of serotonin levels, norepinephrine, and dopamine of transport proteins (Singh & Saadabadi., 2022). Even though the tricyclic antidepressants (TCAs) also work by inhibiting the reuptake of serotonin and norepinephrine in the presynaptic terminal, TCAs tertiary and secondary amines work can be selectively for one or the other. Specifically, Tertiary amines typically exhibit significant serotonin reuptake inhibition, whereas secondary amines display heightened inhibition of norepinephrine uptake (Moraczewski, Awosika, & Aedma., 2023).Venlafaxine can cause side effects such as gastrointestinal complaints, sleep impairment, and sexual dysfunction (Singh & Saadabadi., 2022). In addition, venlafaxine has a black box warning which can increase suicidal ideation which needs thorough education and monitor when patient initially put on the treatment (Singh & Saadabadi., 2022).Aigbogun, M. S., Stellhorn, R., Hartry, A., Baker, R. A., & Fillit, H. (2019). Treatment patterns and burden of behavioral disturbances in patients with dementia in the United States: a claims database analysis. BMC Neurology.Gandhi, K. R., & Saadabadi., A. (2023). Levodopa (L-Dopa). StatPearls.Kumar, A., Gupta, V., & Sharma., S. (2023). Donepezil. StatPearls.Kuns, B., Rosani, A., & Varghese., D. (2022). Memantine. StatPearls.Moraczewski, J., Awosika, A. O., & Aedma., K. K. (2023). Tricyclic Antidepressants. StatPearls.Rosenthal, L. D., & Burchum, J. R. (2019). Lehne’s Pharmacotherapeutics for Advanced Practice Nurses and Physician Assistants. Elsevier.Singh, D., & Saadabadi., A. (2022). Venlafaxine. StatPearls.Singh, H. K., & Saadabadi., A. (2023). Sertraline. StatPearls.Thomas, K., & Saadabadi., A. (2022). Olanzapine. StatPearls.