A, B, C. Hepatotoxicity, including hepatic failure, has been fatal and may more commonly occur in the first 6 months of treatment. Valproic acid and its analogs are contraindicated in patients with known urea cycle disorders. Patients with urea cycle disorders have a genetic enzyme defect leading to an impaired ability to produce urea. Hyperammonemic encephalopathy has been reported following initiation of valproate therapy. Because of, inhibition of the secondary phase of platelet aggregation, and abnormal coagulation parameters complete blood counts and coagulation tests are recommended before initiating valproic acid therapy and at periodic intervals.

B: A variety of drugs have been found to be of some value in the prevention and treatment of vomiting, especially cancer chemotherapy-induced vomiting. With the exception of thioridazine, most of the neuroleptic drugs have antiemetic effects that are mediated by blocking D2 dopaminergic receptors of the chemoreceptor trigger zone of the medulla. Phenothiazines, such as prochlorperazine, were the first drugs shown to be effective antiemetic agents and act by blocking dopamine receptors. They are effective against low to moderately emetogenic chemotherapeutic agents (for example, fluorouracil and doxorubicin). Although increasing the dose improves antiemetic activity, side effects, including hypotension and restlessness, are dose limiting. Other adverse reactions include extrapyramidal symptom and sedation. A: Serotonin 5-HT3 antagonist is incorrect. The specific antagonists of the 5-HT3 receptor, ondansetron and granisetron, selectively block 5-HT3 receptors in the periphery and in the brain (chemoreceptor trigger zone). C: Cannabinoids related is incorrect. Cannabinoids are marijuana derivatives including dronabinol and nabilone and are effective against moderately emetogenic chemotherapy. However, they are seldom first-line antiemetics because of serious side effects. D: Blockage of prostaglandins is incorrect. Dexamethasone and methylprednisolone used alone are effective against mildly to moderately emetogenic chemotherapy. Their antiemetic mechanism is not known, but it may involve blockade of prostaglandins. E: H2 receptor antagonist is incorrect. Antagonists of histamine H2 receptor block the action of histamine at all H2 receptors; their chief clinical use is as inhibitors of gastric acid secretion.

Lecithin is used as a surfactant, not as a preservative. All other listed substances may be used as a preservative in compounding.

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.

Use proton pump inhibitors (PPIs) in patients with or who have risk factors for osteoporosis cautiously. PPIs have been associated with a possible increased risk of bone fractures of the hip, wrist, and spine. Daily treatment with a gastric acid-suppressing medication over a long period of time may lead to hypomagnesemia. Vitamin B12 deficiency has been reported with long term use of PPIs in the literatures. The use of PPIs, may increase the risk of enteric infection by encouraging the growth of gut microflora and increasing susceptibility to organism including Clostridium Difficile. There are recent FDA warnings regarding C. Diff infection with use of PPIs. H. Pylori infection is not a complication of PPIs. PPIs in combination with certain antibiotics are used to treat H. pylori Infections.

Pregnancy test. Tetracyclines are effective in the treatment of severe cases of acne. They are however teratogenic. As such, it is imperative to make sure female patients are not pregnant prior to starting this medication. In many instances patients are started on concurrent birth control to mitigate this risk even further.

A chest x-ray (B) is an important exam to obtain prior to starting drugs which have pulmonary toxicity as a side effect such as amiodarone. A complete blood count (C) would be useful prior to starting a medication that causes anemia, such as immunosuppressive and chemotherapeutic agents. Liver function tests (D) are important to establish as a baseline prior to starting anti-mycobacterial agents. Creatine kinase levels (E) are used to establish as a baseline prior to starting statins.