Week 12: Hematologic Flashcards
Prototype Hematologic (Anti-anemia and Anticoagulation) Drugs
- Ferrous sulfate (Feosol)
- Vitamin B12 (Cyanocobalamin)
- Folic Acid (Folvite)
- Erythropoietin (Epogen)
- Heparin
- Enoxaparin (Lovenox)
- Protamine Sulfate
- Warfarin (Coumadin)
- Vitamin K (AquaMephyton)
- TPA (Alteplase)
- Aminocaproic Acid (Amicar)
- Transexamic Acid (Lysteda)
- Filgrastim (Neupogen)
What varies between iron supplements
the amount of elemental iron found in the salt
ex: Ferrous sulfate has more iron than Ferrous gluconate
Anemia
A SYMPTOM of an underlying problem
Not a diagnosis by itself usually
The most common anemia …
iron deficiency anemia
Prototype Iron Replacement Drug
ferrous sulfate (Feosol)
Ferrous Sulfate (Feosol)
Class: Iron Replacement
Most common med for increasing Fe stores in people
Action of Ferrous Sulfate
Replace iron in the body whihc is then used in normal fxning- ESP. in aiding O2 carrying capacity of RBC
What route is Ferrous Sulfate usually given
Oral
However it can be given parenterally for those who cannot absorb it thorugh the GI tract
What is interesting about the absorption of ferrous sulfate/iron
If body stores of iron are high already less iron absorption will occur. but when the stores are too low it will absorb more easily
___% of ferrous sulfate is absorbed when body stores are low while ___% is absorbed if the stores are high
15%; 2-3%
What are some things that may increase iron absorption
Vitamin C!!!
Orange Juice (Uncertain)
Low Body Stores of Iron
What is interesting about the Metabolism of Ferrous sulfate/iron
Iron is used in the body and is broken down and usually reutilized or stored
VERY LITTLE IS EXCRETED DAY TO DAY d/t ITS IMPORTANCE
Most health people do not lose a lot and do not need much more daily
4 People at risk for Iron Loss/Iron Deficiency Anemia
- Menstruating Women
- Periods when the body is growing - Puberty and INfancy
- GI BLeeding
- Pregnant women
If a patient is found to be anemic one of the first thing that is checked is…
whether there is small or large bleeding occurring in the GI tract and if its iron deficiency anemia
ADRs of Ferrous Sulfate
- Constipation AND Diarrhea
- GI Effects (when taken orally)
Other: HA, Anorexia, Gastric Pain, NV
What is important to know about ferous sulfate therapy following dips in body iron stores
If there is small dips in iron stores there should be improvement within 2-3 weeks
However if there is severe iron loss and anemia (Empty ferratin stores) it could take almost a year to get iron levels back to normal
How often is the dosage of ferrous sulfate usually taken
1 time a day at 325 mg (sometimes 2 but it increases ADRs)
What is important about the stool of someone on ferrous sulfate
Stools will be black (or green) in color and can appear as though is it blood/old blood
It is not, that is staining that occurs
What is an important consideration about solution/liquid iron
Give it through a straw since it can cause staining
Always keep tablet ferrous sulfate…
AWAY FROM CHILDREN - high doses can be lethal
Never take ___ with iron. Why?
Antacids; They will bind oto the iron and carry it out of the body without any of the iron being absorbed
How does the elemental iron content differ between preparations of: Ferrous Sulfate, Ferrous Gluconate, and Dried Ferrous Sulfate
Ferrous Sulfate - 20% elemental iron (ex: 100 mg pill is 20 mg iron)
Ferrous Gluconate - 12%
Dried Ferrous Sulfate - 30%
When is the best time to take your iron supplement
on an empty stomach
*however this can cause NV so someitmes for the first week you take with food then take without after that
Some people cannot take oral iron due to malabsorption syndromes or issues from age, so they may need it IV or IM. What 2 important things need to be kept in mind regarding this route?
- Proper Z Track is needed to prevent skin staining
2. High risk/rate of anaphylaxis when given IV so they must be monitored
deferoxamine (Desferal)
Antidote for iron/ferrous sulfate
it will bind to iron and allow its removal via the kidneys
The biggest problem for Iron supplement adherence is…
the ADRs (GI GI GI - Constipation, Diarrhea, Abdominal Discomfort, NV, etc)
What 2 prototype drugs are included for Macrocytic Anemia treatment
Vitamin B12 (cyanocobalamin)
folic acid (Folvite)
Vitamin B12 (cyanocobalamin)
Oral/Parenteral vitamin that mostly comes from animal products
Used for RBCs AND Myelin Sheathes in the CNS
Action of Vitamin B12
Restores Vitamin B12 to the body which is needed in formation of RBC (and the myelin sheathe)
Where does most Vitamin B12 come from and why is this a problem
animal products - this then is a problem for vegans and vegetarians
Other than RBC what else does Vitamin B12 work on
the myelin sheathes in the CNS
Main Route of Vitamin B12
IM or Deep SubQ (Parenteral)
Oral can be given but the absorption is poor with only 1-2% of uncomplexed B12 absorbing
ADRs of Vitamin B12
RARE - only concern may be a drop in Potassium (K)
What is the 2 issues with a lack of Vitamin B12
RBC - Macrocytic Anemic
Neurological Impairment/Damage
What is needed in order to absorb and use Vitamin B12 effectively
Intrinsic factor for the parietal cells in the stomach and gastric mucosa
So, gastric modification, illness, or surgery can alter B12 absorption
What must be done while first starting Vitamin b12 therapy
patients must be evaluated for 4-6 months to make sure the therapy is effective
If a patient does not have intrinsic factor how must they take Vitamin B12
Large oral doses to have an effect
Megaloblastic/Macrocytic Anemia
An anemia due to deficiency in folic acid or vitamin B12
Causes Large Cell Aenami where there are large RBCs, fewer RBCs, and they are less useful in O2 delivery
Folic Acid (Folvite)
Vitamin
Plays an essential role in DNA production leading to RBC production
In what foods is folic acid found
green leafy vegetables
liver
milk
eggs
In what kinds of people might folic acid levels and absorption be decreased
those with celiac disease
those ingesting large quantities of alcohol
Action of Folic Acid
plays an active role in development of enzymes which are necessary for DNA production
(If inadequate DNA, erythropoiesis is affected and macrocytic RBC occur)
Absorption and Route of Folic Acid
Usually give oral, can be put in TPN as well
Even if someone has malabsorption issues, they can still be given larger doses of this for effect
ADRs of Folic Acid
NONTOXIC
Rare Allergic Rxns can occur
How does dosage differ for folic acid
depends on the situation
For isntance, if a woman is deficient early in pregnancy she may be given a lot more
Once folate stores return to normal, do you need to continue on folic acid supplements?
No once stores return to normal dietary sources are usually adequate in preventing further issues
Folic acid plays a very important part at what stage of development
It plays an important part in the formation of the unborn fetus because it prevents neural tube defects (NTDs)
How did the government plummet the rate of NTDs in the US
In the 1960s they added folic acid to cereal and grain products
Prototype Drug that is a Biological Response Modifier
erythropoietin (Epogen, Procrit)
erythropoietin (Epogen, Procrit) Classification
biological response modifier
recombinant human erythropoietin
Action of erythropoietin
mimics the effect of natrually made erythropoietin - helps production of RBCs
What type of patient may be receiving synthetic erythropoietin regularly
a chronic renal failure patient
What is an illegal use for erythropoietin that can now be detected
professional cyclers may take it to increase RBC and performance
What route is erythropoietin given?
IV - through hemodialysis or Subcutaneously
Parenteral
What is important to know about the absorption of erythropoietin
It is broken down in the GI tract so it has to be given parenterally
ADRs of Erythropoietin
- HTN
- Increased clotting of AV grafts
- Limb pain and sweating up to 12 hours after injection
Other: Cardiovascular Events (Black Box Warning), NVD, SOB, Rash, Cough, Fatigue, Paresthesia, HA, Encephalopathy, Seizure
Black Box Warning of Erythropoietin
Increased incidence of TIA, MI, and CVA (Thromboemboli production)
You are increasing a hypercoagulable state so there is slower moving blood and pooling occurring
Why does erythropoietin cause HTN
because it makes more volume and a more viscous blood volume due to increasing RBC production
What is the dosage of erythropoietin
50-100 U/kg individualized
Why is erythropoietin dosage individualized
to prevent black box issues like thromboemboli formation
What is the % goal for therapeutic erythropoietin use
Maintain a HCT of 30-36%
HCT and HGB rise within 2-6 weeks (Takes a little bit)
Indications for erythropoietin therapy
Chronic Renal Failure
HIV/AIDS (Esp. if tx with Zidovudine)
Adjunct to cancer chemotherapy
Elective non cardiac or non vascular surgery
Why is erythropoietin only given to elective non cardiac or non vascular surgeries
because vascular and cardiac surgeries try to get the blood moving but this makes it slower and more viscous with risk for clotting
erythropoietin is naturally made in the ____
kidneys
What finding should be monitored for and as a result erythropoietin dose should be lowered if it occurs?
Watch for rapid Hct increases (>4 points in 2 weeks) - the dose will need to be lowered as this leaves the patient predisposed to HTN and clotting
What does synthetic erythropoieting response depend on
the endogenous erythropoietin amount in the plasma
At what levels of endogenous erythropoietin will therapeutic use of synthetic erythropoietin be affected
> 500 U/L - syn. ery. will probably not respond
<500 U/L - syn ery will probably respond
Basically if you make a sufficient amount or some amount it works less than if you made none at all
What is needed concurrently with synthetic erythropoietin treatment
adequate iron supplementation!
You cannot make empty RBCs, you need the iron for it as well