Explanation
In older adults, selection of antidepressant medication should be done with various considerations in mind, most notably side effects and risk of drug-drug interactions. The tricyclic antidepressants (TCAs), as discussed on question 50, have various side effects including cardiac conduction abnormalities and drug-drug interactions that make them undesirable for the treatment of depression in older adults. A selective serotonin reuptake inhibitor is more favorable than a TCA in this patient. Fluvoxamine has a high risk for drug-drug interactions, whereas escitalopram does not. Fluvoxamine also has high protein binding, and can therefore interact with anticoagulant medications, such a warfarin. Therefore, of the medications listed, escitalopram is the most appropriate in this patient. In older adults, psychotropic medications should be started at a low dose and titrated up slowly to the lowest effective dose.

Explanation
A: The syndrome is an acute noninflammatory encephalopathy with hepatic failure. Although the etiology of Reye's syndrome is unknown, the condition typically follows viral illness, particularly upper respiratory tract infection (URTI), influenza, varicella, or gastroenteritis, and is associated with aspirin use during the illness. A dramatic decrease in aspirin use in children has made Reye's syndrome rare. High index of suspicion is critical for diagnosis. Consider Reye's syndrome in any child with vomiting and altered mental status. Pathogenesis is unclear, but it typically involves mitochondrial dysfunction in a viral-infected, sensitized host, usually with exposure to mitochondrial toxins (e.g., salicylates, in >80% of cases). Individuals with low levels of urea cycle enzymes are also at increased risk. Mortality has fallen from 50% to less than 20% as a result of earlier diagnosis, recognition of milder cases, and more aggressive therapy. Signs and symptoms of Reye's syndrome include protracted vomiting, with or without significant dehydration, encephalopathy in afebrile patients with minimal or absent jaundice, and hepatomegaly in 50% of patients. Antiemetics may mask early symptoms. Liver function tests reveal elevation of ammonia levels to as much as 1.5 times normal (up to
1200g/dL) 24-48 hours after the onset of mental status changes; this is the most frequent laboratory abnormality. Transaminases (ALT and AST) increase to 3 times normal. Histologic changes include:
hepatocyte cytoplasmic fatty vacuolization, astrocyte edema, loss of neurons, and edema and fatty degeneration in proximal lobules. The American Academy of Pediatrics Committee on Infectious Disease recommends that salicylate not be given to children with chicken pox or influenza B.
B: Acetaminophen is incorrect. Acetaminophen acts by prostaglandin synthesis in the CNS, and this explain its antipyretic and analgesic properties, which account for its weak anti-inflammatory activity. Acetaminophen is a suitable substitute for the analgesic and antipyretic effects of aspirin in those patients with gastric complaints and to avoid Reye's syndrome in children. C: Indomethacin is incorrect. Indomethacin is more potent than aspirin as an anti-inflammatory agent (NSAID), but it is inferior to the salicylates at doses tolerated by rheumatoid arthritis patients. D: Mefenamic acid is incorrect. Mefenamic acid has no advantage over the other NSAIDS as anti- inflammatory agents. The side effects of mefenamic acid, such as diarrhea, can be severe and associated with inflammation of the bowel. E: Diclofenac is incorrect. Diclofenac is approved for long-term use in the treatment of rheumatoid arthritis, osteoarthritis, and ankylosing spondylitis.

Explanation
ABW = 85 kg IBW = 50 kg + 2.3 kg (4) = 59.2 kg 85/59.2 = 1.44 AdjBW = 59.2 kg + 0.4(85 kg-59.2 kg) =
69.52
kg CrCl (IBW) = [(140-84) 59.2]/(72 * 1.4) = 32.8 CrCl (AdjBW) = [(140-84) 69.52]/(72 * 1.4) = 38.6

Explanation/Reference:
Explanation:
If 40mg of amoxicillin are needed per kg of body weight, then the dose of amoxicillin is 40mg multiplied by the patient's body weight. This patient weighs 18 lbs, based on the conversion of 2.2 lbs = 1 kg, the patient weighs
8.2 kg. 40 mg multiplied by 8.2 kg is equal to 328 mg, this is one dose of amoxicillin. If the amoxicillin comes in
250 mg/5 mL, then it needs to be determined how many mLs it will take to get 328 mg of amoxicillin. In order to do this 328 mg needs to be divided by 250 mg to get a ratio. This comes out to be 1.312. This ratio can be multiplied by the number of mLs it takes to make up 250 mg, which is 5 mLs. 1.312 multiplied by 5 mLs is 6.56 mL, this is how many mLs it will take to have 328 mg. This volume is for 1 single dose of amoxicillin. The patient is receiving 2 doses per day and for a total of 10 days, this means the patient will be receiving 20 doses.
20 doses multiplied by 6.56 mL doses equals the total volume the patient will be receiving, which is 131.2 mL.

Explanation
LDL can be elevated by diuretics, cyclosporine, glucocorticoids, and amiodarone.