Post your answers to the 6 questions corresponding to this week’s primary care medication management content. Provide your responses and rationales. Support your rationales with high-level evidence. A 70-year-old woman is in your office complaining of recently having trouble maintaining her balance after taking diazepam (valium). She occasionally takes diazepam when she feels anxious and has trouble sleeping. She has a 15-year history of taking diazepam. Evaluating Balance Issues in a 70-Year-Old Patient Taking Diazepam Evaluating Balance Issues in a 70-Year-Old Patient Taking Diazepam Q1. Explain the cause of this patient’s difficulty in maintaining her balance. Q2. Diazepam experiences a significant first-pass effect. What is the first-pass effect, and how can first-pass metabolism be circumvented? A 75-year-old woman develops symptoms of a cold and buys an over-the-counter cold medication at the grocery store. The medication contains diphenhydramine, acetaminophen, and phenylep
Evaluating Balance Issues in a 70-Year-Old Patient Taking Diazepam
Q1. Difficulties in Maintaining Balance
Diazepam is a benzodiazepine. Its parent molecule and metabolite are pharmacologically active (Khalid et al., 2021). One of its side effects includes ataxia (loss of balance). With increasing age, renal functions and the hepatic clearance for benzodiazepines decrease. This means that the elimination of diazepam is impaired, and thus high blood concentrations increase the risk of developing toxicities such as ataxia. Hire our assignment writing services in case your assignment is devastating you.
Q2. First-pass Effect
First-pass metabolism is a phenomenon whereby a drug is metabolized before reaching systemic circulation when administered orally. Common metabolism sites are the gut wall and the liver. A portion of the metabolized drug can be eliminated in bile. This may reduce the bioavailability of the drug. First-pass metabolism can be circumvented by giving the drug through other routes of administration: intravenously, intramuscularly, intranasally, or in rectal dosage forms (Khalid et al., 2021).
Q3. Signs of Confusion
The likely cause of the patient’s confusion is diphenhydramine. It is a first-generation antihistamine that can be used to treat cold symptoms. It has anticholinergic effects. One of the side effects seen in older adults is confusion (Brenner & Stevens, 2018).
Q4. Warfarin Metabolism
Warfarin is made up of two enantiomorphs, R-warfarin and S-warfarin. These enantiomorphs are metabolized by different pathways using human cytochromes P450 (CYP) enzymes. R-warfarin is mostly metabolized by CYPA12. S-warfarin is metabolized by CYP2C9. Warfarin should not be used in pregnancy because it passes through the placental barrier. This may lead to spontaneous abortions. Warfarin is also teratogenic and may cause birth defects (Warfarin, 2020).
Q5. Hepatic Drug Metabolism of Children 1 Year and Older
A dramatic increase in enzyme levels marks hepatic drug metabolism in children aged one and above. Children have compensatory pathways for drug metabolism, and the metabolism is much higher than in adults. Drug metabolism is slower in infants than in children and adults because the hepatic blood flow and enzymatic pathways in infants are immature (Hogan et al., 2018).
Q6. Protein Binding in the Neonate
In neonates, plasma binding proteins are lower when compared to adults. These proteins gradually increase with age. Albumin in neonates has a lower affinity to bilirubin, which may result in easy displacement of bilirubin from albumin. This may cause clinical jaundice. Drug binding should be considered when prescribing highly protein-bound drugs.
References
Brenner, G. M., & Stevens, C. W. (2018). Pharmacology. Elsevier.
Hogan, M. A., Burke, S. O., Gingrich, M. M., & Dentlinger, N. C. (2018). Pharmacology. Pearson Education, Inc.
Khalid, S., Rasool, M. F., Imran, I., Majeed, A., Saeed, H., Rehman, A. ur, Ashraf, W., Ahmad, T., Bin Jardan, Y. A., & Alqahtani, F. (2021). A physiologically based pharmacokinetic model for predicting diazepam pharmacokinetics after intravenous, oral, intranasal, and rectal applications. Pharmaceutics, 13(9), 1480. https://doi.org/10.3390/pharmaceutics13091480
Warfarin. (2020). In LiverTox: Clinical and Research Information on Drug-Induced Liver Injury. National Institute of Diabetes and Digestive and Kidney Diseases.