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starzs9
06-19-2008, 06:43 PM
Hi,
Post some calculations and formulas on Pharmacokinetics and any other calculations which would be good for all test takers as a last Minute Review.
Spare some time for this please.
I will start with simple calculation:

1)A DESIRED STATE PLASMA LEVEL OF THEOPHYLLINE IS 15mg/L.AVERAGE T1/2 OF THEOPHYLLINE IS 4hrs,APPARENT VOLUME OF DISTRIBUTION IS 25L.
What is infusion nessary?

Kel=0.693/t1/2
Kel=0.693/4=0.175
K0=Kel*Cp*VL=0.175*15*25=63.8mg/hr.

2)Cpss=K0/Cl

3)CL=Kel*V

4)Total Body clearence
Total body clearance, CL, can be separated into clearance due to renal elimination, CLr and clearance due to metabolism, CLm.
Total body clearance, CL, can be separated into clearance due to renal elimination, CLr and clearance due to metabolism, CLm.
CLr = ke * V (renal clearance) and
CLm = km * V (metabolic clearance)
CL = CLr + CLm

5)LOADING DOSE CAN BE CALCULATED FROM:
Cp0=Dose/V
Dose=V*Cp0

starzs9
06-19-2008, 07:42 PM
APPARENT VOLUME OF DISTRIBUTION:

Vd=Db/Cp

Vd-Volume of distribution.
Db-Amount of drug in the body
Cp-Plasma concentration of drug in body.

starzs9
06-19-2008, 07:46 PM
ENZYME INDUCERS:
Rifampin
CBZ
Phenobarbitol.
Phenytoin
Nicotine.
Rifabutin.

ENZYME INHIBITORS:
Cimentidine.
Ciprofloxacin.
Erythromycin.
Clopidrogel.
Ketoconazole.
Fluvoxamine.
Nelfinavir.
Ritonavir.

pinky786
06-19-2008, 07:59 PM
Hi Starzs9!

Goodwork, just want to add , Carbamazepine is the only one which is also a self inducer, that is increase its own metabolism.

Buffer capacity = 0.576 x c

t 90% = 0.152 x t 1/2

Reaching 90%, 95%, 99% without Loading dose ( D L) takes 3.32 , 4.32 , 6.65 half-lives respectively.

Keep up the all good work and Goodluck.

pinky786

starzs9
06-19-2008, 08:01 PM
RENAL CLEARENCE:

Clr=Cu*Vu/Cp

Clr=Creatinin clearence of drug
Cu=Concentration of drug in Urine.
Cp=Concentration of drug in plasma.
Vu=Total volume of urine in time(t)

Normal Glomerlar filtration is 120ml/minutes

starzs9
06-19-2008, 08:03 PM
Hi Pinky,
Thanks.It was new information for me..So CBZ is "SELF INDUCER".
Keep posting guys.
Goodluck.
God bless.

starzs9
06-19-2008, 09:23 PM
ZERO ORDER REACTION:
-dc/dt=K

FIRST ORDER REACTION:
Log Co/C=Kt/2.303
C0-Concentration of reactant at time t=0
C=Concentration of reactant at time t
t=time.
t1/2=0.693/k

SECOUND ORDER REACTION:
dx/dt=k(a-x)(b-x)
a-concentration of reactant A at time t
b-concentration of reactant B at time t
dx/dt=rate of reaction.
k=reaction constant
K=1/t * x/a(a-x)

t1/2=1/ka

pinky786
06-19-2008, 11:08 PM
Hi!

Important to remember few things,

Aminoglycosides + Furosemide (loop diruretics) = Increased Ototoxicity

Aminogylcosides + Cephalosporins = Increased Nephrotoxixity.

Only Tetracycline that can be used in Renal Impaired patients = Doxycycline

Demecocycline used in SIADH (Syndrome of Inappropriate Anti diuretic hormone)

Floroquinolone main side effect on CNS.

Chloremphenicol main side effects = Hemolytic Anemia and Graybaby Syndrome.

Goodluck.

pinky786

starzs9
06-20-2008, 12:00 AM
LOADING DOSE:
DL=Css *Vd
DL-Loading dose of drug
Css-Steady state plasma concentration.
Vd-Volume of distribution.

ABSOULTE BIOAVALIBILITY:
AUCpo(ORAL ADMINISTRATION)/AUCiv(IV ADMINISTRATION)

RELATIVE BIOAVALIBILITY:
AUCtest/AUCstandred.


CLr=Ke*Vd
CLr-Renal clearence
Ke-elimination constant.
Vd-Volume of distribution.

CLt=K*Vd
CLt-Total body clearence.
K-elimination constant.
Vd-volume of distribution.

Css=R/Vd*K
R-Rate of infusion.
Vd-volume of distribution.
K-elimination constant.


AUC=F*Do/K*Vd
F-Fraction of the drug absorbed
Do-Dose of the drug.
K-Elimination constant.
Vd-volume of distribution.

starzs9
06-20-2008, 01:33 AM
Metabolic acidosis:
Loss of BICARBONATE from body.
Metabolic Alkalosis:
Increase in BICARBONATE concentration.
Respiratory Acidosis:
Inadequet ventilation of CO2 by the lung.
Respiratory Alkalosis:
Increase in excretion of CO2

pinky786
06-20-2008, 03:36 AM
Electrolytes:

Normal Values For Potassium = 3.5 - 5.0 mEq/L
Normal Values For Calcium = 135 - 147 mEq/L
Normal Values For Chloride = 95 - 105 mEq/L
Normal Values For Bicarbonate = 22 - 28 mEq/L

Minerals:

Normal Values For Calcium = 8.8 - 10.3 mg/dl or 2.20 - 2.56 mmol/L
Normal Values For Magnesium = 1.6 - 2.4 mEq/L or 0.8 - 1.20 mmol/L
Normal Values For Phosphate = 2.5 5.0 mg/dl or 0.8 - 1.60 mmol/L

Sodium is Extracellular Cation
Potassium is Intracellular Cation

Chloride is Extracellular Anion
Phospahte is Intracellular Anion.

starzs9
06-20-2008, 04:35 AM
Accuracy
is a measure of how close a number is to the actual value (how far from the actual value a particular measurement falls). In many experiments, accuracy cannot be determined; only an estimate of the accuracy can be found, because the actual value is not known.

Precision
refers to how close repeated measurements are to each other (a measure of the variation present in a set of readings

T-test:

the t-test assesses whether the means of two groups are statistically different from each other

variable :
is any entity that can take on different values

chi-square test
A chi-square test may be applied on a contingency table for testing a null hypothesis of independence of rows and columns

F-test
is any statistical test in which the test statistic has an F-distribution if the null hypothesis is true.

starzs9
06-20-2008, 04:37 AM
validity
the term refers to the degree to which a study supports the intended conclusion drawn from the results.
MEDIAN OR MODE
Median or Mode is generally expressed as a middle value of experiment, if number of values are even, then average of middle values should be considered. To find median or mode of experiment data, one should first arrange the data in ascending or descending order

pinky786
06-20-2008, 05:08 AM
Hi Starzs9!

Good Job, what I read about median and mode is , median in the middle value when you arranged the data, if odd number the middle value is median ,if even , add the two middle and divide by two, but the mode is the value that occurs the most frequently in a data set (http://en.wikipedia.org/wiki/Data_set) or a probability distribution (http://en.wikipedia.org/wiki/Probability_distribution). So Median and Mode are two different terms, correct me if I am wrong, I know in Mannon he used it everywhere together.

Goodluck.

Pinky786

pharmacystudent2001
06-20-2008, 02:08 PM
Hi pinky,
You are right. Median and Mode are different. I got them from my statistics class.
In manan, they are the same

starzs9
06-20-2008, 03:26 PM
Hi pinky,
Thanks for correction,i found in one notes.Just copied it.
Thanks again.

realgk
06-20-2008, 03:53 PM
Hi everyone,

If median and mode are different, how would you calculate when asked for mode in the question. Do you look for the number that appears more frequently in the data set

Realgk???

Shams
06-20-2008, 04:06 PM
Hey...

Thankyou for these quick notes!! they are great!!
Water Soluble Vitamins:-
Thiamine (B1)
Niacin (B3)
Cyanocobalamin(B12)
Riboflavin(B2)
Pyridoxine(B6)
Ascorbic Acid
Folic Acid
Pentothenic Acid
Biotin

Lipid Soluble Vitamins:-
Retinol (A)
Ergocalciferol (D)
Alpha-tocopherol (E)
Phytonadione (K)

Shams

realgk
06-20-2008, 04:20 PM
1. Standard deviation (SD) is sqaure root of variance
2. Coefficient of variance or relative standard deviation = SD/x (x is mean)

What are parametric and non parametric tests? Can someone explain those

pinky786
06-20-2008, 04:43 PM
Hi Realgk!

Parametrics are Mean, Standard Deviation and T-Distribution.
Non-Parametrics are Mode, Median, Chi-Square.

Goodluck.

pinky786

MN2000
06-20-2008, 05:15 PM
Question,

What is the initial change in total body weight when beginning TPN, increase in:
1- lean body mass weight only

MN2000
06-20-2008, 05:17 PM
2- lean body mass&total water body weight
3-total body water only
4-total fat only

janis70
06-20-2008, 05:35 PM
I think the increase is due of increase in fluid. In CPR defines total body water as an estimative of lean body mass (pag 1130), so I'm confused.
If I have to pick one, I'll pick lean body mass only.
Please correct me if i"m wrong.
Thanks

janis70
06-20-2008, 05:38 PM
Another question:
Multipledose container cannot contain a volume of injection more than sufficient to permit the withdrawal administration of:
10ml , 30 ml , 50 ml or 100 ml.
Thanks in advance

pinky786
06-20-2008, 05:58 PM
Hi MN2000!

Maybe this can help Elsevier Article Locator (http://linkinghub.elsevier.com/retrieve/pii/S0899900798000537)
If I have to pick I will pick 2, that both the body weight as well as Lean body mass will change.

Goodluck.

pinky786

jvvora
06-20-2008, 06:13 PM
Hi Pinky,

In manan shroff book,

parametric statistics are mean, SD, and T-tests
Non parametric statistics are mode, median and chi square tests.

So which is right? Please correct me.

starzs9
06-20-2008, 06:16 PM
Hi Janis,
It looks like 30ml.
Good luck.

starzs9
06-20-2008, 06:19 PM
DILUENTS:
L M SQUARE S
L-Lactose
M square: Microcrystalline cellulose,Mannitol.
S-Sorbitol.
Binders:
Acacia
Gelatin
Glucose
Tragacanth
Starch.
Disintergrents:
Starch
Cellulose
Glidants:
Talc
Corn Starch
Silica dervitives

pinky786
06-20-2008, 06:26 PM
Hi Jvvora!

You are right my mistake sorry :)

Goodluck.

starzs9
06-20-2008, 06:29 PM
common herbs:
1)Chamomile
Chamomile is often used in the form of a tea as a sedative.
Close monitoring is recommended for patients who are taking medications to prevent blood clotting (anticoagulants) such as warfarin.
2)Echinacea
Echinacea has been touted to be able to boost the body's ability to fight off infection.
Echinacea can cause liver toxicity
It should be avoided in combination with other medications that can affect the liver (such as ketaconazole, leflunomide (Arava), methotrexate (Rheumatrex), isoniazide (Nizoral
3)St. John's Wort
herbal treatment for depression, anxiety, and sleep disorders
St. John's wort may also leave nerve changes in sunburned areas
St. John's wort can also cause headaches, dizziness, sweating, and agitation when used in combination with serotonin reuptake inhibitor medications such as fluoxetine (Prozac) and paroxetine (Paxil).
4)Garlic
Garlic has been used to lower blood pressure and cholesterol
Garlic may decrease normal blood clotting and should be used with caution in patients taking medications to prevent blood clotting (anticoagulants) such as warfarin /Coumadin.
5)Ginko Biloba
This herb is very popular as a treatment for dementia
not recommended to be taken with aspirin, nonsteroidal anti-inflammatory drugs (Advil), naproxen (Aleve) or Motrin), or medications to prevent blood clotting (anticoagulants) such as warfarin (Coumadin). Ginko should be avoided in patients with epilepsy taking seizure medicines, such as phenytoin (Dilantin), carbamazepine (Tegretol), and phenobarbital.
6)Ginseng
Ginseng has been used to stimulate the adrenal gland, and thereby increase energy
beneficial effect on reducing blood sugar .in patients with diabetes mellitus
Its use in pregnancy is not recommended
avoided in patients taking aspirin, nonsteroidal antiinflammatory drugs (such as ibuprofen (Advil), naproxen (Aleve) or Motrin), or medications to prevent blood clotting (anticoagulants) such as warfarin (Coumadin)
7)Ginger
Ginger may lead to blood thinning.
It is not recommended to be taken with medications that prevent blood clotting (anticoagulants) such as warfarin (Coumadin).
8)Black Cohosh
natural way to treat menopausal symptoms

Shams
06-20-2008, 06:38 PM
Just to add to your list starz...

St.Johns wart is also a potent inducer as well as smoking and chronic alcohol use.

Grapefruit is an inhibitor..it interacts with many medications e.g. Statins, Cyclosporin,nifedipine.

shams

MN2000
06-20-2008, 07:01 PM
Hi Pinky,

I am still confused, according to the article the gaining of weight all over the study period, what about the initial change of weight in the beginning of TPN? & as Janis70 said In CPR defines total body water as an estimative of lean body mass.what do you think the best answer will be?

pinky786
06-20-2008, 07:02 PM
Thaizides Diuretics cause Hypokalemia, Hyponatremia, Hypercalcemia, Hyperurecemia, Hyperglycemia, should not be given in Gout patients and in Diabetes and also if creatinine clearence is less than 50ml/min.

Loop Diuretics are prefered choice in renal failure and also in hypercalcemia as they cause hypcalcemia. They cause Ototoxicity, the least ototoxic in the group is Bumetanide.

Aminoglycoside + loop diuretics = Increased Ototoxicity.

starzs9
06-20-2008, 07:23 PM
IMMUNOLOGY:
substance which evoke immunse response "IMMUNOGEN"
IMMUNOGEN+ANTIBODY=ANTIGEN.
ANTIBODY+ANTIGEN=HAPTONS OR EPITOPES OR DETERMINANTS
IMMUNOGENS are like about 10,000 daltons.
Immunogens are "PROTEINS"
PENCILLIN(ALONE)=antigenic and poorly immunogenic.
PENCILLIN+PROTEIN=HIGHLY IMMUNOGENIC.


IGE-ALLERGIC DISEASES.
IGM,IGD-BETA GLOBULIN.
IGG,IGA-GAMMA GLOBULIN.
B-CELLS-IGG ANTIBODIES.
IgD-DIFFERENTIAL B-LYMPHOCYTES.

B-LYMPHOCYTES----Mature in Bone marrow.
T-LYMPHOCYTES----MATURE IN THYMUS.

TYPES OF REACTONS:

TYPE I
Immediate
allergic hypersensitive.
within 5 min
IgE,IgG
Basophils and mast cells are involved.

TYPE II
Cytotoxic reactions.
primarly mediated by IgG,IgM and complemet.
examples:
HEMOLYTIC ANEMIA
ERYTHROBLASTOSIS FETALIS
GOOD PASTURE SUNDROME.
GRAVES DISEASE.
MYASTHENIA GRAVIS
TRANSFUSION REACTIONS.

TYPE III
Complex reactions
IgG,IgM,IgA.IgD
Examples:
Serum sicknes
RA
SLE
Vasculitis
Lymphadenopathy

TYPE IV
Delayed hypersensitivity reactions
Cell mediated immunity
Mediated by T-Lymphocytes,Lymphocytes
Delayed by 24-72hrs./
Examples:
TB
Graft rejection.
Organ rejection

pinky786
06-20-2008, 07:50 PM
Cell Mediated Immunity = Involve T Lymphocytes and does not involve antibodies or compliment for initiation rather involve Macrophages, NK-Cells and Cytotoxic T-cell.

Humoral Mediated Immunity = Involve B lymphocyes mediated and requires Compliment and initiation.

Innate Immune System = Non Specific Immunity = provide Immediate Defense.

Adaptive Immune System = Long term Immunity = Involve T-cells and B-cells.

Shams
06-20-2008, 08:20 PM
Receptors and Function:-

Alpha 1:- Constriction of blood vessels that supply to skin and mucosa.
alpha 1 Blockers:- prazosin doxazosin (good vasodilators!)

Alpha 2:- prevents release of noradrenalin = Reduce blood pressure
Alpha 2 STIMULATORS:- Clonidine, Methyldopa

Beta 1:-Found within myocardium, increase myocardial conduction speed, force and rate.
Stimulators:- Digoxin,dopamine

Beta 2:- Relaxation of smooth muscle and blood vessels that supply skeletal muscles.
Beta-agonists (Stimulation):- Albuterol

shams

starzs9
06-20-2008, 08:47 PM
Phamaceutical Marketing:

Marketing plan consists of
Analysis of marketing environment(External factors).
Analysis of practise(Internal factore)

Added phamacy services
New clinical services.
Disease state mangment programme.
Drug information services.

Key elements of marketing plan included
Competitive analysis(SWOT analysis).
Goal statement.
Target marketing.
Marketing mix.
Control.
SWOT analysis:Used to assess the internal strengths and weakness of the phamacy in contest with the oppurtunity and threat that may exisist in its external environment)
S-Strength of the practise(Internal environment).
O-Oppurtunities of the practise(External environment)
W-Weakness of the practisess(Internal environment)
T-threats to the practice(External environment)

Market research techniques include:
telephone survey.
Questionnaries.
Published data.
casual conversation


Marketing research re UPDATED every:annual update

In a ADOPTION GROUP smallest percentage of customers belong to:INNOVATORS.
Innovators.-less than 5%
Early adopters-10-15%
Late adopters-15-20%
Early majority-30-35%
Late majority-30-35%

Which GROUP accepts new services early in Marketing services-Early adopters.

Phamacist controls:
Marketing Mix

4P'S of marketing.PRODUCT,PLACE,PROMOTION,PLACE.

Marketing tools such as below help the pharmcist and phamacy staff in providing publicity of products
Brochers.
Flers.
Bag stuffers.

janis70
06-20-2008, 10:03 PM
Hi MN 2000,
About the parenteral nutrition question, I just talked to a physician friend and he told me the increase is because of total body water only, especially in the beginning.(the pourpose of the parenteral nutricion is give the caloric needs to mantein the patient)
My confusion was because the CPR defines this as an estimate of lean body mass, but lean body mass include everything less fat...
So, the answer would be : total body water only.
Maybe I'm still wrong, but it makes sense

janis70
06-20-2008, 10:06 PM
anyone with another opinion???????????
Please, help with this confusion (TPN and increase with weight)

realgk
06-20-2008, 10:34 PM
Hi everyone,

1. Multiple dose containers contain not more than 30 ml.
2. When u begin the TPN initially, only the total body water will increase.

Thanks and all the best to everyone appearing for the exam

realgk
06-20-2008, 10:50 PM
Hi Pinky.

I read that Bumetanide has the maximum chances of causing ototoxicity. Please confirm the same

pinky786
06-20-2008, 11:28 PM
Hi realgk!

I read it in the Q & A By Manon and there was specific question that out of all which cause the least ototoxicity.

Now that is becoming so confusing, God Bless us all.

pinky786

realgk
06-20-2008, 11:43 PM
Hi Pinky,

Do u remember the question number in M.S

MN2000
06-21-2008, 12:24 AM
Hi janis70,

First, thanks for asking and search for the right answer.
Second, it make sense that only the total body water will increase in the beginning,so i will go with this answer till now.

Thanks Realgk for reply and for everyone try to find the answer.

Good luck everyone.

pinky786
06-21-2008, 04:18 AM
Hi Realgk!

I cannot recall exactly the question number cause when I read that I wrote it on the book, if you have any reference that says that Bumetanide is more Ototoxic please share it with us.

Thanks in advance.

pinky786

realgk
06-21-2008, 08:10 PM
Hi Pinly,

I cannot figure out the reference at present, but i had made a note of it in my notes. And yes after looking at the question in Manan shroff. But even i cant recall which question it was. But i guess, dont worry, i think the choice will be Bumetanide in a given set, since thats the only drug that is unique

pinky786
06-23-2008, 01:06 PM
Hi Realgk!

I found that question, its in Rx Exams CD's For FPGEE. In the 5th CD, section 2, there is a question which of the following is the least Ototoxic of all ? , and the answer is Bumetanide.

Goodluck

pinky786

realgk
06-23-2008, 02:50 PM
Hi Pinky,

Thanks for the confirmation. I noted down that as most toxic by mistake . Thanks for the correction

pinky786
06-23-2008, 04:51 PM
Hi Realgk!

Good that we are clear on that and good thing that we won't forget it now for a long time :)

Goodluck.

pinky786

jvvora
06-24-2008, 10:09 PM
Can someone give a brief note on linear and non linear pharmacokinetics with zero and first order differences? Please....that will be a great help in clearing all confusions which I have.

jvvora

starzs9
06-25-2008, 04:28 PM
ENHANCEMENT OF DRUG EFFECTS:
Addition:
Occurs when two DIFFERENT drugs with same effect are given toghther resulting in a adrug effect that is equal in magnitude to the sum of individual effects of two drugs.
example:Trimethoprim/sulfamethosone.

SYNERGISM:
occurs when two drugs with same effect are given toghther,producing a drug effect that is greater in megnitude than sum of the individual effects of 2 drugs.
example:pencillin,gentamycin

POTENTIATION:
when one drug lacking an effect of its own,increases the effect of another drug that is active.
example:carbidopa

jvvora
06-25-2008, 05:38 PM
I Have One Qhestion Related To Calculation.

Mean Of 100 Observations Is 34. Out Of All 100 Observations 25% Of Observations Has Maximum Of 29.5. Find Out Median.

1) 25 Percentile
2) 50 Percentile
3) 75 Percentile.

I Do Not Have Right Answer With Me. But I Don't Know How Can You Calculate It?

pinky786
08-17-2008, 06:26 AM
December 2008 takers!

This might be useful for you all.

successfpgee
11-01-2008, 04:50 AM
Hi,
I don't want all these previous test takers effort go vain,so iam bringing this up.
Thanks june 2008 test members.

Alahmmed
11-01-2008, 07:41 AM
Hi,
Post some calculations and formulas on Pharmacokinetics and any other calculations which would be good for all test takers as a last Minute Review.
Spare some time for this please.
I will start with simple calculation:

1)A DESIRED STATE PLASMA LEVEL OF THEOPHYLLINE IS 15mg/L.AVERAGE T1/2 OF THEOPHYLLINE IS 4hrs,APPARENT VOLUME OF DISTRIBUTION IS 25L.
What is infusion nessary?

Kel=0.693/t1/2
Kel=0.693/4=0.175
K0=Kel*Cp*VL=0.175*15*25=63.8mg/hr.

2)Cpss=K0/Cl

3)CL=Kel*V

4)Total Body clearence
Total body clearance, CL, can be separated into clearance due to renal elimination, CLr and clearance due to metabolism, CLm.
Total body clearance, CL, can be separated into clearance due to renal elimination, CLr and clearance due to metabolism, CLm.
CLr = ke * V (renal clearance) and
CLm = km * V (metabolic clearance)
CL = CLr + CLm

5)LOADING DOSE CAN BE CALCULATED FROM:
Cp0=Dose/V
Dose=V*Cp0




Hello StarZ,

Would you please do me a huge favor and explain these for me, i can't get the K0 meaning, and most of the letters, i really hate kinetics can you imagine up till now i didn't even start with this section.

thank you in advance.

fpgeelady
11-01-2008, 04:54 PM
thank you guys for all your efforts[clap] goodluck to you all

ptausa
11-14-2008, 10:57 AM
Parametric Tests
-----------------
standard deviation
standard score
students' t-test
paired t -test
two sample t-test
ANOVA
normal curve test
mean
p

Non Parametric Test (Distribution free ststistics)
-------------------
Chi-square test
madian
mode
sign test
runs test
sperman's rho

successfpgee
12-04-2008, 08:13 PM
Bringing this Up!:tup::p

f-pharma2008
01-25-2009, 11:37 PM
Thanks pinky, starzs and everyone else :tup:

BOTICAGIRL
01-26-2009, 02:13 AM
This is a very helpful informations. Thanks in a million. Goodluck to all who will take the exam this April.