Hepatic disease can significantly impact drug pharmacokinetics by altering metabolism and excretion of drugs. The liver metabolizes many drugs through enzyme systems that may be impaired in diseases like cirrhosis and hepatitis. This can cause drug accumulation, changes in active metabolites, and altered protein binding. While laboratory tests can detect liver damage, no single test assesses total liver function. The Child-Pugh score is used to classify the severity of hepatic impairment. For drugs that are highly metabolized by the liver, dosage may need to be reduced based on the Child-Pugh score to avoid toxicity. The degree of dosage adjustment depends on the individual drug's pharmacokinetics and the patient's liver function status.
THIS SLIDE GIVES AN INSIGHT TO THE DIFFERENT METHODS THAT COULD BE USED FOR THE DOSAGE ADJUSTMENT IN PATIENTS WITH RENAL DISEASE.
RENAL FUNCTION OF THE PATIENT IS ASSESSED TO DETERMINE THE DOSAGE ADJUSTMENT
Therapeutic drug monitoring (TDM) of drugs used in seizure disordersAbel C. Mathew
Therapeutic drug monitoring (TDM) of drugs used in seizure disorders- Phenytoin, Valproic acid, Carbamazepine are major drugs used in epilepsy disorders. These drug need TDM to ensure their proper usage.
THIS SLIDE GIVES AN INSIGHT TO THE DIFFERENT METHODS THAT COULD BE USED FOR THE DOSAGE ADJUSTMENT IN PATIENTS WITH RENAL DISEASE.
RENAL FUNCTION OF THE PATIENT IS ASSESSED TO DETERMINE THE DOSAGE ADJUSTMENT
Therapeutic drug monitoring (TDM) of drugs used in seizure disordersAbel C. Mathew
Therapeutic drug monitoring (TDM) of drugs used in seizure disorders- Phenytoin, Valproic acid, Carbamazepine are major drugs used in epilepsy disorders. These drug need TDM to ensure their proper usage.
Nomograms and tabulations in design of dosage regimens pavithra vinayak
Nomograms and tabulations in the design of dosage regimens --- NOMOGRAM IN UREMIC PATIENTS: NOMOGRAM FOR RELATIONSHIP BETWEEN CREATININE CLEARANCE AND ELIMINATION RATE CONSTANT FOR FOUR DRUGS clinical pharmacokinetics and therapeutic drug monitoring ---fifth PharmD notes
In this presentation I have tried to explain in brief about the dosage adjustment in renal disorders, how to carry out this process and the important formulae which are used in it.
Population pharmacokinetics is the study of the sources and correlates of variability in drug concentrations among individuals who are the target patient population receiving clinically relevant doses of a drug of interest
Bayesian theory in population pharmacokinetics--
1) INTRODUCTION TO BAYESIAN THEORY
2)BAYESIAN PROBABILITY TO DOSING OF DRUGS
3)APPLICATIONS AND USES OF BAYESIAN THEORY IN APPLIED PHARMACOKINETICS:
therapeutic drug monitoring and clinical pharmacokinetics-fifth pharm d notes
conversion from INTRAVENOUS TO ORAL DOSING----- design of dosage regimenpavithra vinayak
conversion from INTRAVENOUS TO ORAL DOSING----- TYPES OF IV TO PO THERAPY CONVERSIONS: MEDICATIONS INCLUDED IN AN IV TO PO CONVERSION PROGRAM: SELECTION OF PATIENTS FOR IV TO PO THERAPY CONVERSION: design of dosage regimen--clinical pharmacokinetics and therapeutic drug monitoring-- fifth pharm D notes
Clinical pharmacokinetics and its application--
1)definition
2) APPLICATIONS OF CLINICAL PHARMACOKINETICS
Design of dosage regimens:
a) Nomograms and Tabulations in designing dosage regimen,
b) Conversion from intravenous to oral dosing,
c) Determination of dose and dosing intervals,
d) Drug dosing in the elderly and pediatrics and obese patients.
Pharmacokinetics of Drug Interaction:
a) Pharmacokinetic drug interactions
b) Inhibition and Induction of Drug metabolism
c) Inhibition of Biliary Excretion.
Therapeutic Drug monitoring:
a) Introduction
b) Individualization of drug dosage regimen (Variability – Genetic, Age and Weight, disease, Interacting drugs).
c) Indications for TDM. Protocol for TDM.
d) Pharmacokinetic/Pharmacodynamic Correlation in drug therapy.
e) TDM of drugs used in the following disease conditions: cardiovascular disease, Seizure disorders, Psychiatric conditions, and Organ transplantations
Dosage adjustment in Renal and Hepatic Disease.
a. Renal impairment
b. Pharmacokinetic considerations
c. General approach for dosage adjustment in renal disease.
d. Measurement of Glomerular Filtration rate and creatinine clearance.
e. Dosage adjustment for uremic patients.
f. Extracorporeal removal of drugs.
g. Effect of Hepatic disease on pharmacokinetics.
Population Pharmacokinetics.
a) Introduction to Bayesian Theory.
b) Adaptive method or Dosing with feedback.
c) Analysis of Population pharmacokinetic Data
Definition and scope of Pharmacoepidemiology ABUBAKRANSARI2
In these slides I shared the information of definition and scope of pharmacoepidemiology. Types of studies - cohort studies, cross-sectional studies etc.
Variation of Pharmacokinetics in disease states-converted-converted.pdfUVAS
I am a pharmacist. These slides describe biotechnology topic. I hope students get more benefits about it. These slides very helpful for the pharmacy department students.
Nomograms and tabulations in design of dosage regimens pavithra vinayak
Nomograms and tabulations in the design of dosage regimens --- NOMOGRAM IN UREMIC PATIENTS: NOMOGRAM FOR RELATIONSHIP BETWEEN CREATININE CLEARANCE AND ELIMINATION RATE CONSTANT FOR FOUR DRUGS clinical pharmacokinetics and therapeutic drug monitoring ---fifth PharmD notes
In this presentation I have tried to explain in brief about the dosage adjustment in renal disorders, how to carry out this process and the important formulae which are used in it.
Population pharmacokinetics is the study of the sources and correlates of variability in drug concentrations among individuals who are the target patient population receiving clinically relevant doses of a drug of interest
Bayesian theory in population pharmacokinetics--
1) INTRODUCTION TO BAYESIAN THEORY
2)BAYESIAN PROBABILITY TO DOSING OF DRUGS
3)APPLICATIONS AND USES OF BAYESIAN THEORY IN APPLIED PHARMACOKINETICS:
therapeutic drug monitoring and clinical pharmacokinetics-fifth pharm d notes
conversion from INTRAVENOUS TO ORAL DOSING----- design of dosage regimenpavithra vinayak
conversion from INTRAVENOUS TO ORAL DOSING----- TYPES OF IV TO PO THERAPY CONVERSIONS: MEDICATIONS INCLUDED IN AN IV TO PO CONVERSION PROGRAM: SELECTION OF PATIENTS FOR IV TO PO THERAPY CONVERSION: design of dosage regimen--clinical pharmacokinetics and therapeutic drug monitoring-- fifth pharm D notes
Clinical pharmacokinetics and its application--
1)definition
2) APPLICATIONS OF CLINICAL PHARMACOKINETICS
Design of dosage regimens:
a) Nomograms and Tabulations in designing dosage regimen,
b) Conversion from intravenous to oral dosing,
c) Determination of dose and dosing intervals,
d) Drug dosing in the elderly and pediatrics and obese patients.
Pharmacokinetics of Drug Interaction:
a) Pharmacokinetic drug interactions
b) Inhibition and Induction of Drug metabolism
c) Inhibition of Biliary Excretion.
Therapeutic Drug monitoring:
a) Introduction
b) Individualization of drug dosage regimen (Variability – Genetic, Age and Weight, disease, Interacting drugs).
c) Indications for TDM. Protocol for TDM.
d) Pharmacokinetic/Pharmacodynamic Correlation in drug therapy.
e) TDM of drugs used in the following disease conditions: cardiovascular disease, Seizure disorders, Psychiatric conditions, and Organ transplantations
Dosage adjustment in Renal and Hepatic Disease.
a. Renal impairment
b. Pharmacokinetic considerations
c. General approach for dosage adjustment in renal disease.
d. Measurement of Glomerular Filtration rate and creatinine clearance.
e. Dosage adjustment for uremic patients.
f. Extracorporeal removal of drugs.
g. Effect of Hepatic disease on pharmacokinetics.
Population Pharmacokinetics.
a) Introduction to Bayesian Theory.
b) Adaptive method or Dosing with feedback.
c) Analysis of Population pharmacokinetic Data
Definition and scope of Pharmacoepidemiology ABUBAKRANSARI2
In these slides I shared the information of definition and scope of pharmacoepidemiology. Types of studies - cohort studies, cross-sectional studies etc.
Variation of Pharmacokinetics in disease states-converted-converted.pdfUVAS
I am a pharmacist. These slides describe biotechnology topic. I hope students get more benefits about it. These slides very helpful for the pharmacy department students.
Title: Clinical Pharmacy: Enhancing Patient Care through Medication Optimization
Description:
Welcome to the world of Clinical Pharmacy, where pharmaceutical expertise meets patient-centered care! In this SlideShare presentation, we dive into the fascinating realm of Clinical Pharmacy, exploring its vital role in healthcare and how it contributes to improved patient outcomes.
Clinical Pharmacy is an evolving field that combines the knowledge of pharmacology and therapeutics with direct patient care. It focuses on the optimization of medication therapy to ensure safe, effective, and personalized treatment regimens for patients of all ages. This SlideShare presentation provides a comprehensive overview of Clinical Pharmacy, highlighting its significance in modern healthcare settings.
Within this presentation, we explore the key pillars of Clinical Pharmacy, including:
1. Medication Therapy Management: Discover how Clinical Pharmacists work collaboratively with healthcare teams to optimize medication therapy. Learn about the process of medication reconciliation, drug therapy monitoring, and medication counseling to enhance patient adherence and safety.
2. Pharmacotherapy Expertise: Gain insights into the in-depth knowledge of Clinical Pharmacists in pharmacology, drug interactions, and pharmacokinetics. Understand how this expertise helps them make evidence-based decisions, select appropriate medications, and customize treatment plans to individual patient needs.
3. Translational Research: Explore the role of Clinical Pharmacists in conducting research to bridge the gap between scientific discoveries and clinical practice. Learn how they contribute to the development and evaluation of new therapies, ensuring their safety, efficacy, and cost-effectiveness.
4. Interprofessional Collaboration: Recognize the importance of collaboration among healthcare providers in achieving optimal patient outcomes. Explore how Clinical Pharmacists actively engage with physicians, nurses, and other healthcare professionals to provide comprehensive patient care.
5. Patient Education and Advocacy: Delve into the patient-centered approach of Clinical Pharmacy, emphasizing the significance of patient education, shared decision-making, and promoting medication adherence. Understand how Clinical Pharmacists empower patients to actively participate in their treatment plans.
By the end of this SlideShare presentation, you will have a deeper understanding of Clinical Pharmacy's multifaceted nature and its pivotal role in enhancing patient care. Whether you are a healthcare professional seeking to expand your knowledge or a curious individual interested in the intersection of pharmacy and patient care, this presentation is an excellent resource to explore the exciting world of Clinical Pharmacy.
Join us on this enlightening journey, and let Clinical Pharmacy open doors to new perspectives and possibilities for improved patient outcomes and healthcare excellence.
Pharmacokinetics variations in Disease States.Faizan Akram
The biggest issue in PK/PD and drug therapy is variability in
response. Variability factors that affect pharmacokinetics and pharmacodynamics influence clinical trials and dose regimen designs.
Similar to Effects of Liver disease on Pharmacokinetics (20)
Announcement about my previous presentations - Thank youAreej Abu Hanieh
ANNOUNCEMENT Thank you for all of you, my followers who sent me messages with a lot of love and appreciations, I finally graduated after 6 years of studying in Birzeit University , In doctor of Pharmacy department I hope all of you benefited from all the presentations posted before Thank you a new PharmD GraduatedAreej ^^
Ozempic: Preoperative Management of Patients on GLP-1 Receptor Agonists Saeid Safari
Preoperative Management of Patients on GLP-1 Receptor Agonists like Ozempic and Semiglutide
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NYSORA Guideline
2 Case Reports of Gastric Ultrasound
Lung Cancer: Artificial Intelligence, Synergetics, Complex System Analysis, S...Oleg Kshivets
RESULTS: Overall life span (LS) was 2252.1±1742.5 days and cumulative 5-year survival (5YS) reached 73.2%, 10 years – 64.8%, 20 years – 42.5%. 513 LCP lived more than 5 years (LS=3124.6±1525.6 days), 148 LCP – more than 10 years (LS=5054.4±1504.1 days).199 LCP died because of LC (LS=562.7±374.5 days). 5YS of LCP after bi/lobectomies was significantly superior in comparison with LCP after pneumonectomies (78.1% vs.63.7%, P=0.00001 by log-rank test). AT significantly improved 5YS (66.3% vs. 34.8%) (P=0.00000 by log-rank test) only for LCP with N1-2. Cox modeling displayed that 5YS of LCP significantly depended on: phase transition (PT) early-invasive LC in terms of synergetics, PT N0—N12, cell ratio factors (ratio between cancer cells- CC and blood cells subpopulations), G1-3, histology, glucose, AT, blood cell circuit, prothrombin index, heparin tolerance, recalcification time (P=0.000-0.038). Neural networks, genetic algorithm selection and bootstrap simulation revealed relationships between 5YS and PT early-invasive LC (rank=1), PT N0—N12 (rank=2), thrombocytes/CC (3), erythrocytes/CC (4), eosinophils/CC (5), healthy cells/CC (6), lymphocytes/CC (7), segmented neutrophils/CC (8), stick neutrophils/CC (9), monocytes/CC (10); leucocytes/CC (11). Correct prediction of 5YS was 100% by neural networks computing (area under ROC curve=1.0; error=0.0).
CONCLUSIONS: 5YS of LCP after radical procedures significantly depended on: 1) PT early-invasive cancer; 2) PT N0--N12; 3) cell ratio factors; 4) blood cell circuit; 5) biochemical factors; 6) hemostasis system; 7) AT; 8) LC characteristics; 9) LC cell dynamics; 10) surgery type: lobectomy/pneumonectomy; 11) anthropometric data. Optimal diagnosis and treatment strategies for LC are: 1) screening and early detection of LC; 2) availability of experienced thoracic surgeons because of complexity of radical procedures; 3) aggressive en block surgery and adequate lymph node dissection for completeness; 4) precise prediction; 5) adjuvant chemoimmunoradiotherapy for LCP with unfavorable prognosis.
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New Directions in Targeted Therapeutic Approaches for Older Adults With Mantl...i3 Health
i3 Health is pleased to make the speaker slides from this activity available for use as a non-accredited self-study or teaching resource.
This slide deck presented by Dr. Kami Maddocks, Professor-Clinical in the Division of Hematology and
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STATEMENT OF NEED
Mantle cell lymphoma (MCL) is a rare, aggressive B-cell non-Hodgkin lymphoma (NHL) accounting for 5% to 7% of all lymphomas. Its prognosis ranges from indolent disease that does not require treatment for years to very aggressive disease, which is associated with poor survival (Silkenstedt et al, 2021). Typically, MCL is diagnosed at advanced stage and in older patients who cannot tolerate intensive therapy (NCCN, 2022). Although recent advances have slightly increased remission rates, recurrence and relapse remain very common, leading to a median overall survival between 3 and 6 years (LLS, 2021). Though there are several effective options, progress is still needed towards establishing an accepted frontline approach for MCL (Castellino et al, 2022). Treatment selection and management of MCL are complicated by the heterogeneity of prognosis, advanced age and comorbidities of patients, and lack of an established standard approach for treatment, making it vital that clinicians be familiar with the latest research and advances in this area. In this activity chaired by Michael Wang, MD, Professor in the Department of Lymphoma & Myeloma at MD Anderson Cancer Center, expert faculty will discuss prognostic factors informing treatment, the promising results of recent trials in new therapeutic approaches, and the implications of treatment resistance in therapeutic selection for MCL.
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Hematology/oncology fellows, attending faculty, and other health care professionals involved in the treatment of patients with mantle cell lymphoma (MCL).
Learning Objectives
1.) Identify clinical and biological prognostic factors that can guide treatment decision making for older adults with MCL
2.) Evaluate emerging data on targeted therapeutic approaches for treatment-naive and relapsed/refractory MCL and their applicability to older adults
3.) Assess mechanisms of resistance to targeted therapies for MCL and their implications for treatment selection
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2. • Hepatic disease can alter drug pharmacokinetics and pharmacodynamics.
• Hepatic disease may include common hepatic diseases, such as
• alcoholic liver disease (cirrhosis) and
• chronic infections with hepatitis viruses B and C,
• and less common diseases, such as
• acute hepatitis D or E,
• primary biliary cirrhosis,
• primary sclerosing cholangitis, and
• a1-antitrypsin deficiency
• In addition, drug-induced hepatotoxicity is the leading cause of acute liver failure in
the United States (Chang and Schiano, 2007).
3. • Drugs are often metabolized by one or more enzymes located in cellular membranes in
different parts of the liver.
• Drugs and metabolites may also be excreted by biliary secretion.
•
• Hepatic disease may lead to
• drug accumulation,
• failure to form an active or inactive metabolite,
• increased bioavailability after oral administration,
• and other effects including possible alteration in drug–protein binding.
• Liver disease may also alter kidney function, which can lead to accumulation of a drug
and its metabolites even when the liver is not primarily responsible for elimination.
4. • The major difficulty in estimating hepatic clearance in patients with hepatic
disease is the complexity and stratification of the liver enzyme systems.
• In contrast, creatinine clearance has been used successfully to measure
kidney function and renal clearance of drugs.
• Clinical laboratory tests measure only a limited number of liver functions.
• Some clinical laboratory tests, such as the aspartate aminotransferase
(AST) and alanine aminotransferases (ALT), are common serum enzyme
tests that detect liver cell damage rather than liver function.
5. • Other laboratory tests, such as serum bilirubin, are used to measure
biliary obstruction or interference with bile flow.
• Presently, no single test accurately assesses the total liver function.
• Usually, a series of clinical laboratory tests are used in clinical practice
to detect the presence of liver disease, distinguish among different
types of liver disorders, gauge the extent of known liver damage, and
follow the response to treatment.
6. • A few tests have been used to relate the severity of hepatic impairment to
predicted changes in the pharmacokinetic profile of a drug (FDA Guidance
for Industry, 2003).
• Examples of these tests include the ability of the liver to eliminate marker
drugs such as antipyrine, indocyanine green, monoethylglycine-xylidide,
and galactose.
• Furthermore, endogenous substrates, such as albumin or bilirubin, or a
functional measure, such as prothrombin time, has been used for the
evaluation of liver impairment.
7. Dosage Considerations in Hepatic Disease
• Several physiologic and pharmacokinetic factors are relevant in considering
dosage of a drug in patients with hepatic disease (Table 24-10).
• Chronic disease or tissue injury may change the accessibility of some enzymes as
a result of redirection or detour of hepatic blood circulation.
• Liver disease affects the quantitative and qualitative synthesis of albumin,
globulins, and other circulating plasma proteins that subsequently affect plasma
drug protein binding and distribution.
• As mentioned, most liver function tests indicate only that the liver has been
damaged; they do not assess the function of the cytochrome P-450 enzymes or
intrinsic clearance by the liver.
8.
9. • Because there is no readily available measure of hepatic function that
can be applied to calculate appropriate doses, enzyme-dependent
drugs are usually given to patients with hepatic failure in half-doses,
or less.
• Response or plasma levels then must be monitored.
• Drugs with flow-dependent clearance are avoided if possible in
patients with liver failure.
10. Fraction of Drug Metabolized
• Drug elimination in the body may be divided into
• (1) fraction of drug excretion unchanged, fe, and
• (2) fraction of drug metabolized.
• The latter is usually estimated from 1 – fe;
• alternatively, the fraction of drug metabolized may be estimated from
the ratio of Clh/Cl, where Clh is hepatic clearance and Cl is total body
clearance.
11. PRACTICE PROBLEM
• The hepatic clearance of a drug in a patient is reduced by 50% due to
chronic viral hepatitis.
• How is the total body clearance of the drug affected?
• What should be the new dose of the drug for the patient?
• Assume that renal drug clearance (fe = 0.4) and plasma drug protein
binding are not altered.
12. Active Drug and the Metabolite
• (1) when the drug is more potent than the metabolite, the overall
pharmacologic activity will increase in the hepatic-impaired patient
because the parent drug concentration will be higher;
• (2) when the drug is less potent than the metabolite, the overall
pharmacologic activity in the hepatic patient will decrease because
less of the active metabolite is formed.
13. Hepatic Blood Flow and Intrinsic Clearance
• Blood flow changes can occur in patients with chronic liver disease.
• Hepatic arterial-venous shunts may lead to reduced fraction of drug
extracted and an increase in the bioavailability of drug.
• In other patients, resistance to blood flow may be increased as a
result of tissue damage and fibrosis, causing a reduction in intrinsic
hepatic clearance.
14. • The following equation may be applied to estimate hepatic clearance
of a drug after assessing changes in blood flow and intrinsic clearance
(Clint):
15. Pathophysiologic Assessment
• In practice, patient information about changes in hepatic blood flow
may not be available, because special electromagnetic or ultrasound
techniques are required to measure blood flow and are not routinely
available.
• The clinician/ pharmacist may have to make an empirical estimate of
the blood flow change after examining the patient and reviewing the
available liver function tests.
16. approaches to assess hepatic impairment
• The Child–Pugh (or Child–Turcotte–Pugh) score assesses the overall
hepatic impairment as mild, moderate, or severe (Figg et al, 1995;
Lucey et al, 1997).
• The score employs five clinical measures of liver disease, including
• total bilirubin,
• serum albumin,
• International Normalized Ratio (INR),
• ascites, and
• hepatic encephalopathy
17.
18. • chronic hepatic disease is more likely to change the metabolism of a
drug than acute hepatitis
• Chronic liver disease has been shown to decrease the metabolism of
many drugs as shown in Table 24-13.
• However, the amount of decrease in metabolism is difficult to assess.
19.
20. Hepatic Impairment and Dose Adjustment
• Drugs that have the following properties are less likely to need dosage
adjustment in patients with hepatic impairment (FDA Guidance for
Industry, 2003)
1. The drug is excreted entirely via renal routes of elimination with no
involvement of the liver.
2. The drug is metabolized in the liver to a small extent (<20%), and the
therapeutic range of the drug is wide, so that modest impairment of
hepatic clearance will not lead to toxicity of the drug directly or by
increasing its interaction with other drugs.
3. The drug is gaseous or volatile, and the drug and its active metabolites
are primarily eliminated via the lungs.
21. • For each drug case, the physician needs to assess the degree of hepatic
impairment and consider the known pharmacokinetics and
pharmacodynamics of the drug.
• For example, Mallikaarjun et al (2008) studied the effects of hepatic or
renal impairment on the pharmacokinetics of aripiprazole (Abilify), an
atypical antipsychotic used to treat schizophrenia. These investigators
concluded that there were no meaningful differences in aripiprazole
pharmacokinetics between groups of subjects with normal hepatic or renal
function and those with either hepatic or renal impairment. Thus, the
adjustment of the aripiprazole does not appear to be required in
populations with hepatic or renal impairment.
22. • In contrast, Muirhead et al (2002) studied the effects of age and renal and
hepatic impairments on the pharmacokinetics, tolerability, and safety of
sildenafil (Viagra), a drug used to treat erectile dysfunction. Muirhead et al
(2002) observed significant differences in Cmax and AUC between the
young and the elderly subjects for both the parent drug and the
metabolite. In addition, the hepatic impairment study demonstrated that
pharmacokinetics of sildenafil was altered in subjects with chronic stable
cirrhosis, as shown by a 46% reduction in CL/F and a 47% increase in Cmax
compared with subjects with normal hepatic function. Sildenafil
pharmacokinetics was affected by age and by renal and hepatic
impairments, suggesting that a lower starting dose of 25 mg should be
considered for patients with severely compromised renal or hepatic
function.
23. Adjustment based on Child-Pugh score
• The Child-Pugh score for a patient with normal liver function is 5
• while the score for a patient with grossly abnormal serum albumin,
total bilirubin, and prothrombin time values in addition to severe
ascites and hepatic encephalopathy is 15.
24. • A Child-Pugh score equal to 8-9 is grounds for a moderate decrease (∼
25%) in initial daily drug dose for agents that are primarily (≥60%)
hepatically metabolized,
• and a score of 10 or greater indicates that a significant decrease in initial
daily dose (∼ 50%) is required for drugs that are mostly liver metabolized.
• As in any patient with or without liver dysfunction, initial doses are meant
as starting points for dosage titration based on patient response and
avoidance of adverse effects.
25. • For example, the usual dose of a medication that is 95% liver
metabolized is 500 mg every 6 hours, and the total daily dose is 2000
mg/d.
• For a hepatic cirrhosis patient with a Child-Pugh score of 12, an
appropriate initial dose would be 50% of the usual dose or 1000
mg/d. The drug could be prescribed to the patient as 250 mg every 6
hours or 500 mg every 12 hours. The patient would be closely
monitored for pharmacologic and toxic effects due to the medication,
and the dose would be modified as needed.