FARMAKOLOGI KLINIK Rahmatini Bagian Farmakologi Terapi Fakultas Kedokteran
FARMAKOLOGI KLINIK Rahmatini Bagian Farmakologi & Terapi Fakultas Kedokteran Universitas Andalas
DEFINISI WHO ( 1988) Disiplin dalam bidang kedokteran berdasarkan prinsip ilmiah, menyatukan keahlian farmakologi & keahlian klinik dengan tujuan meningkatkan manfaat & keamanan obat
TUJUAN FARMAKOLOGI KLINIK Terapi Efektif, Aman , Rasional
RATIONAL DRUG USE Ratio Benefit – Risk - Cost F. Kinetika F Dinamika F Ekonomi
PHARMACOLOGICAL ASPECTS IN CLINICAL PRACTICE Pharmacokinetic Pharmacodynamic How drugs act The dynamics of drug conc. in the body * Absorption / bioavailability * Distribution * Biotransformation * Excretion
THERAPEUTIC DRUG MONITORING (TDM)
Measuring the plasma drug conc. Provide useful information about the adequacy of the dosage regimen or the likehood toxicity
Therapeutic Drug Monitoring (TDM) Ph dynamic Ph kinetic Druginteraction • Measuring/ interpreting plasma drug conc. • Therapeutic response • Side effects • Toxic effects
Time-drug conc. relationship Drug conc. (mg/l) 40 30 Drug toxicity 20 Therapeutic level 10 m. e. c Low therapy 1 2 Time (hour) 3 4
Therapeutic Drug Monitoring (TDM) 1. Narrow margin of safety drugs 2. Drugs for prevention/ therapy of life threatening diseases or life saving drugs 3. Difficulty in ditinguishing between the effects of a disease and the toxic effects of a drug 4. Potent drugs drug amount is very small 5. Drugs that show variability of drug conc. in plasma
Factors that modify drug plasma concentration for a given dose • Drug formulation • Drug interaction • Environmental factors • Genetic variation • Renal and hepatic function
Reasons for monitoring drug treatment 1. To see whethere is therapeutic response 2. To assess drug toxicity 3. To assess compliance
DRUG DIGOXIN THERAPEUTIC 0, 0010 -0, 0022 µg/ml TOXIC > 0, 0025 DIPHENYLHI DANTOIN 10 - 20 > 25 LIDOCAIN 1, 5 -5 >9 PHENOBARBITAL 15 -30 > 40 THEOPHYLINE 10 -20 > 20
Examples of difficulty in ditinguishing between the effects of a disease and the toxic effects of a drug 1. Digoxin toxicity Congest. Heart Failure Nausea / anorexia / arrythmias 2. Gentamycin toxicity Gram (–) septicaemia Renal damage
Drugs- plasma conc. Pharmacokinetic parameters Cmax (peak) Half life AUC 24 Time Cmin (trough)
Visualisation of half-life First order elimination of a drug (t ½ : 2 hours) Drug conc. (mg/l) 20 10 The plasma conc. falls by half each half-life t½ t½ 5 t½ 2. 5 2 Hours 4 6
Clinical application of half life (t½) * Designing drug dosage regimen * Determining time to reach steady state drug level which show clinical effect * Determining time to reach the drug level which have no clinical effect anymore
CONSIDERATION Ph’kinetic Ph’dynamic Ph’economic RATIONAL & GOOD CLINICAL THERAPY
SESUNGGUHNYA BAGIMU, ADA MALAIKAT- MALAIKAT YANG SELALU MENGAWASI PEKERJAANMU QS 82 : 10
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