Diabetes medications: Difference between revisions
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==Biguanides== | ==Biguanides== | ||
# | #E.g. Metformin, buformin | ||
# | #Metformin does not cause wt gain like sulfonyls | ||
#Effect is to decrease hep glucose prod, inhibit intestinal glucose absorption | |||
# | ##Also decreases fatty acid oxidation | ||
# | #Increases insulin sensitivity and decreases insulin resistance | ||
# | #Decrease sugar of DM pt not same as nl person so is antihyperglycemic agent not hypoglycemic agent | ||
# | |||
#100% renal excretion | #100% renal excretion | ||
# | #Most serious side effect is lactic acidosis due to increased lactate production | ||
# | #Signs of lactic acidosis | ||
# | ##Nausea/vomiting, abd pain, sleepy, tachypnia, lethargy | ||
##Seen mostly if renal/ liver dz, alcohol, heart dz, infection | |||
#Metformin exclusion criteria | |||
##CRI, cardiac/ pulm insuff, h/o lactosis, profound infectionc, liver dz, alcohol, iv contrast agents | |||
#fatality from metformn lactosis not related to lactate levels or metformin level but rather to concomitant condition (hypoxia) resulting in elevated lactate | #fatality from metformn lactosis not related to lactate levels or metformin level but rather to concomitant condition (hypoxia) resulting in elevated lactate | ||
#OD- hypoglycemia rare, can get lactosis- obs for 6-8 hr and tx c bicarb and consider hemodialysis | #OD- hypoglycemia rare, can get lactosis- obs for 6-8 hr and tx c bicarb and consider hemodialysis |
Revision as of 06:45, 27 September 2011
Background
- Hypoglycemics
- Sulfonylureas
- Benzoic acid derivatives
- Antihyperglycemics
- Biguanides
- Alpha glucosidase inhibitors
- Thiazolidinediones
Insulin
Sulfonylureas
- increase insulin secretion and enhance activity
- second and third gen sulfonyls are lipid soluble so penetrate cell mem better and have selective binding
- stimulate insulin release from panc beta cells by inhibiting atp dependent potassium channel.
- Decrease hepatic insulin clearance= increase insulin conc
- Elevated insulin level feeds back to liver and causes decrease hepatic gluc prod
- Secondary treatment failure from noncompliance, wt gain, desensitized beta cells, and escalating insulin resistance and increased insulin deficiency
- Sulfon has hepatic metab, renal exretion and prolonged activity
- Toxicity related to hypoglycemia
- Risk factors for hypoG- elderly, poor diet, alcohol, renal/ hepatic dz, polypharmacy
- Time to peak effect and duration of effect important in OD
- Chlorpropamide, glyburide and glypizide most likely to cause hypoG
- Do not use glyburide in pt with CRI since renally excreted
- If pt well and young, will not get hypoG during fast due to counterregulatory hormones for glucose homeostasis
- Chlorpropamide can cause hyponatremia regardless of dose- induces ADH secretion- risk increases with elderly and if on thiazide diuretics
- Chlorpropamide can also give cholestatic jaundice, resolves with discontinuation
- Glypizide- enterohepatic recirculation- prolonged action if liver dz. Long duration of action since metabolite still active. All metabolites renally cleared
Biguanides
- E.g. Metformin, buformin
- Metformin does not cause wt gain like sulfonyls
- Effect is to decrease hep glucose prod, inhibit intestinal glucose absorption
- Also decreases fatty acid oxidation
- Increases insulin sensitivity and decreases insulin resistance
- Decrease sugar of DM pt not same as nl person so is antihyperglycemic agent not hypoglycemic agent
- 100% renal excretion
- Most serious side effect is lactic acidosis due to increased lactate production
- Signs of lactic acidosis
- Nausea/vomiting, abd pain, sleepy, tachypnia, lethargy
- Seen mostly if renal/ liver dz, alcohol, heart dz, infection
- Metformin exclusion criteria
- CRI, cardiac/ pulm insuff, h/o lactosis, profound infectionc, liver dz, alcohol, iv contrast agents
- fatality from metformn lactosis not related to lactate levels or metformin level but rather to concomitant condition (hypoxia) resulting in elevated lactate
- OD- hypoglycemia rare, can get lactosis- obs for 6-8 hr and tx c bicarb and consider hemodialysis
Alpha Glucosidase Inhibitors
- acarbose, miglitol, voglibose
- competitively and reversibly inhibit alpha glucosidase brush border hydrolase enzyme- makes postprandial decrease in carbohydrate absorption since complex polysaccharides not broken down into absorbable monosaccharides
- does not affect lactose absorption
- if hypoG- sucrose/ table sugar will not work- use glucose- po or iv
- take these meds with each meal with first bite
- since limited aborption, stays in gut and side effects mostly GI- bloating, gas, diarrhea
- contraindications- cirrhosis, IBD, malabsorption synd
- alpha glucs do not cause hypoG when used as monotx
- acarbose- can cause transaminitis/ liver inj
- since min absorption- systemic tox from OD unlikely
Thiazolidinediones
- rosiglitazone and poiglitazone
- enhance insulin effect on muscle, fat, liver without increasing panc insulin secretion
- protein bound and hep metab- not good if liver dz
- side effects- induce ovulation, increase plasma vol bad if CHF, decrease effectiveness of OCP's
Benzoic Acid Derivatives
- repaglinide- mono or combo tx c metformin
- binds to atp dependent potassium channel like sulfonyls but at different site.
- Unlike sulfonyls, it decreases insulin lvls
- Dose 30 min before meal to decrease post prandial hyperglycemia
Source
6/06 MISTRY