renal pharmacology 2 Flashcards
4 relevant types of drugs
altering urine pH drugs
altering excretion of organic molecule drugs
drugs for treating urinary tract disorders
drugs for treating renal failure
healthy urine pH
6
the urine’s pH is slightly acidic due to the metabolites - 3
urea
ureic acid
createnine
pH altering drugs can change the pH of urine to
5-8.5
what causes acidification of urine - 4
meat heavy diet
sodium heavy diet
metabolic acidosis - excessive bicarbonate loss
thiazide diuretics
what causes alkination of urine - 3
citrus fruit -heavy diet
respiratory alkalosis
urinary tract infection as bacteria converts urea to ammonia
patients with ___ urine may be more susceptible to UTIs
alkali
clinical benefits of alkaline urine - 5
antibacterial
improves dysuria (difficult urination)
inhibits urinary stone formation
solubilisation of weak acid drugs
enables excretion of toxic substances
example where drug excretion is effected by urine pH
methamphetamine - acidic urine = more excretion in less time
less in alkaline urine
carbonic anhydrase inhibitors
convert carbon dioxide and water intocarbonic acid, protons, bicarbonate ions - so may be used as diuretic
stop bicarbonate reabsorption in nephron
inc bicarbonate excretion so inc urine pH
sodium bicarbonate can be used to treat __ overdose
salicylate
carbonic anhydrase inhibitor example
acetazolamide
carbonic anhydrase inhibitor - when does tolerance develop
after 3 days
citrate admin
oral as Na and K salts
calcium citrate treats
calcium deficiency
potassium citrate treats
renal tubular acidosis (kidney stone formation)
citrate metabolism is via
citric acid/ Krebs cycle
excretes bicarbonate resulting in alkaline urine
at what point in the krebs cycle does citrate feed in
when citrate converted to isocitrate via aconitase
drugs that alter the excretion of organic molecules are particularly relevant in treatment of
gout
what is gout
form of acute arthritis
causes uric acid crystal formal in joints due to accumulation
what is gout caused by
hyperuricaemia - serum uric acid level of larger than 404micromol per L
what is gout exacerbated by - 3
alcohol consumption
meat consumption
diuretic ise
what is hyperuricaemia
serum uric acid level of larger than 404micromol per L
gout is more common in which sex
men
as inc consumption of meat, alcohol vs women
kidneys are an important __ of uric acid secretion
regulator
approx __% of uric acid is secreted by kidneys
65%
approx __% of uric acid is secreted by intestine
35%
how is uric acid formed
through the catabolism of purines
uric acid excretion via kidneys pathway
uric acid passes into glomerular filtrate
then most reabsorbed in proximal tubule
small amount excreted into tubule via an anionic secreting mechanism
small amount excreted into tubule via an anionic secreting mechanism. how much?
8-12% filtered urate is excreted
treatment focus to treat gout
inc elimination of urate
types of drugs used to treat gout by inc elimination of urate - 2
uricosuric agents
inhibition of urate synthesis
examples of uricosuric agents used to treat gout by inc elimination of urate - 2
probenecid
sulfinpyrazone
examples of drugs used to treat gout by inc elimination of urate that inhibit urate synthesis
allopurinol
probenecid inhibits
penicillin excretion
when using uricosuric agents, uric acid excretion
decreases before it begins to increase - nike tick shape on graph hehe