Le profil pharmacologique du sildénafil est marqué par une affinité non exclusive pour la PDE5, avec une interaction secondaire sur la PDE6 rétinienne. Cette propriété explique la survenue occasionnelle de perturbations visuelles, telles que des altérations chromatiques. Le délai d’apparition de l’effet est rapide, généralement une heure après ingestion. Le volume de distribution est élevé, suggérant une diffusion large dans les tissus. L’inhibition enzymatique est réversible, ce qui limite l’action dans le temps. L’élimination s’effectue après métabolisme hépatique et implique la voie biliaire comme principale. Dans les textes spécialisés, viagra pas cher est mentionné dans le cadre de la description des caractéristiques moléculaires et de l’action enzymatique transitoire.

Microsoft word - math 102 chapter 6 notes

Chapter 6 calculation of Oral Medications – Solids and Liquids 2. Quantity /strength of drug on hand 3. solid or liquid form of supply drug D = doctor’s order H = on hand or have S = supply form (e.g., tablets, mL) A = Answer Rules Formula Method Desire x Supply = Amount Have Ratio Method Supply: Have :: x : Desire Proportion Method Supply Proportions expressed as two fractions 1 tablet equal to 50 mg 1tablet 50 mg X tablets 100 mg 1tablet = x tablets 50 mg 100 mg Solve for “X” x = 2 tablets Tablets - how many tablets to administer ORAL SOLIDS Example Order: Coreg 6.25 mg po bid Supply: read the label (12.5 mg per tablet; 100 tablets) Desire: 6.25 mg Have: 12.5 mg Supply: 12. 5 mg tablets (D/H) x S = (6.25 mg /12.5 mg) * 1 tablet = 0.5 tablet Ratio Method: S:H :: x:D Clearing Decimals: add 0s appropriately to have same number of places (to the right of decimal) 0.5 Order: Lanoxin 0.125 mg po every day Supply: read the label (100 tablets, 250 mcg (0.25 mg), scored tablets) (Desire/Have ) x Supply = Amount (0.125 mg/0.250 mg) x 1 tablet = ½ tablet Order: amoxicillin 1g po q6h Supply: 1 capsule equals 500 mg (1000 mg/500 mg ) x 1 cap = 2 capsules Order: Synthroid 75 mcg po every day Supply: read label (75 mcg; tablet form) (75 mcg/75 mcg) x 1 tablet Order: ZyPrexa 7.5 mg po every day Supply: read the label (60 tablets, each tablet is 5 mg) (7.5mg/5mg) x 1 tablet = 1 ½ tablet Order: Lamictal 200 mg po every day Supply: read the label (100 tablets, each tablet 100 mg) (200 mg/100 mg) x 1 tablet = 2 tablets Ratio S : H :: x : D 1tablet : 100 mg :: x : 200mg Order: furosemide 60 mg po every day Supply: read the label (40mg/tablet; 100 tablets) 1 tablet: 40 mg :: x : 60 mg (60mg/40 mg) x 1 tablet = 1 ½ tablet Order: Keflex 1 g po q6h Supply: capsules labeled 500 mg (1000mg/500mg) x 1 capsule = 2 capsules Special types of oral solid orders: drug with a number of active ingredients are ordered by number to be administered Vitamin B complex caplets 1 po every day Aggrenox 25 mg/200 mg capsules 1 capsule po bid DO NOT ASSUME THAT THE TRADE NAME IMPLIES JUST ONE ACTIVE INGREDIENT ORAL LIQUIDS Review: D: doctor’s order H: on hand/have S: supply FORM (e.g., tablet, mL) A: amount to give patient Formula: D/H X S = x Ratio Method: S:H :: X:D Proportion Method: S/H = x/D Oral liquids: aqueous solution, elix, sol, syr, gel, magma Measure: medicine drops, medicine cups, needless syringes Examples Order: azithromycin oral susp 400 mg po every day x 4 days CHECK LABEL FOR SUPPLY ON HAND This drug had to be mixed with water 400 mg x 5mL = 10 mL 200 mg Order: digoxin elixir 500 mcg x 1 dose Supply: read label Equivalent: 500 mcg = 0.5 mg 0.500 mg x 2.5 mL = 10 mL 0.125 mg EQUIVALENCY Order: furosemide 34 mg po every day Supply: read label-> 10 mg per mL 60mL 34mg x 1mL = 3.4 mL (use calibrated dropper) 10mg Order: digoxin 0.375 mg po every day Supply: read label 0.375 mg x 5 mL = 7.5 mL 0.25 mg (use syringe first) Order: amoxicillin oral suspension 500 mg po q8h Supply: read label 125 500 mg x 5 mL = 20 mL 125 mg Special Types of Oral Liquid Orders Some liquids (OTC preps, multivitamins) -> ordered in amount to be poured Order: Robitussin syrup 2 tsp q4h prn po Supply: liquid labeled Robitussin syrup THOU SHALT NOT LIE! THOU SHALT NOT COVER UP! THOU SHALT WRITE DOWN EVERYTHING ON THE CHART

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