Suresh Pichandi et al. / Int J Cur Sci Res. 2011; 1(2): 47 - 56.
52
to an increased potential for drug interactions and problems with
certain foods (such as grapefruit juice). Pitavastatin appears to be
a substrate of CYP2C9,and not CYP3A4 (which is a common source
of interactions in other statins). As a result, pitavastatin is less
likely to interact with drugs that are metabolized via CYP3A4,
which might be important for elderly patients who need to take
multiple medicines[12].
Pitavastatin is used together with a proper diet to treat high
cholesterol levels and high triglyceride (fat) levels in the blood.
High levels of cholesterol or triglycerides can clog blood vessels
and cause medical problems. Pitavastatin may help prevent some
medical problems that are caused by clogged blood vessels.
Pitavastatin belongs to the group of medicines called HMG-CoA
reductase inhibitors or "statins". It works by blocking an enzyme
that is needed by the body to make cholesterol. This reduces the
amount of cholesterol in the blood.
8.Pravastatin
Pravastatin (marketed as Pravachol or Selektine) is a member of
the drug class of statins, used for lowering cholesterol and
preventing cardiovascular disease. Initially known as CS-514, it
was originally identified in a bacterium called Nocardia
autotrophica. Pravastatin is a cholesterol-lowering medication
that blocks the production of cholesterol (a type of fat) in the body.
Pravastatin reduces low-density lipoprotein (LDL) cholesterol and
total cholesterol in the blood. Lowering your cholesterol can help
prevent heart disease and hardening of the arteries, conditions
that can lead to heart attack, stroke, and vascular disease.
Pravastatin is used to treat high cholesterol. Pravastatin is also
used to lower the risk of stroke, heart attack, or other heart
complications in people with coronary heart disease. The most
common side effects of pravastatin Nausea and vomiting,
Headache, Diarrhea, Unexplained rash, Fatigue, Dizziness, Muscle
pain. The active beta-hydroxy acid form of the 3-hydroxy-3-
methylglutaryl coenzyme A (HMG-CoA) reductase inhibitors
competitively inhibits the enzyme HMG-CoA reductasem.
Inhibition of HMG-CoA reductase prevents conversion of HMG-
CoA to mevalonate, the rate-limiting step in cholesterol
biosynthesis. The primary site of action of HMG-CoA reductase
inhibitors is the liver.Inhibition of cholesterol synthesis in the liver
leads to upregulation of LDL receptors and an increase in
catabolism of LDL cholesterol. There may also be some reduction
in LDL production as a result of inhibition of hepatic synthesis of
very low-density lipoprotein (VLDL), the precursor of LDL. HMG-
CoA reductase inhibitors reduce LDL cholesterol, VLDL
cholesterol, and to a lesser extent, plasma triglyceride
concentrations, and slightly increase high-density lipoprotein
(HDL) concentrations[13].
9.Simvastatin
Simvastatin is a hypolipidemic drug used to control elevated
cholesterol, or hypercholesterolemia.Simvastatin is a member of
the statin class of pharmaceuticals, is a synthetic derivate of a
fermentation product of Aspergillus terreus.It is marketed under
the trade names Zocor, Simlup, Simcard, Simvacor. The development
of simvastatin was closely linked with lovastatin.Simvastatin is a
powerful lipid-lowering drug that can decrease low density
lipoprotein (LDL) levels by up to 50%. It is used in doses of 5 mg up
to 80 mg. Higher doses (160 mg) have been found to be too toxic,
while giving only minimal benefit in terms of lipid lowering.In
secondary prevention,80 mg per day reduced major cardiovascular
events.
All statins act by inhibiting 3-hydroxy-3-methylglutaryl
coenzyme A HMG-CoA reductase,the rate-limiting enzyme of the
HMG-CoA reductase pathway,the metabolic pathway responsible
for the endogenous production of cholesterol.Statins are more
effective than other lipid-regulating drugs at lowering LDL-
cholesterol concentration but they are less effective than the
fibrates in reducing triglyceride concentration. However, statins
reduce cardiovascular disease events and total mortality
irrespective of the initial cholesterol concentration. In the blood,
statins lower total and LDL ("bad") cholesterol as well as
triglycerides. LDL cholesterol is believed to be an important cause of
coronary artery disease. Lowering LDL cholesterol levels slows and
may even reverse coronary artery disease. Statins also increase HDL
("good") cholesterol. Raising HDL cholesterol levels, like lowering
LDL cholesterol may slow coronary artery disease.
In patients with coronary heart disease, diabetes peripheral
vessel disease or history of stroke or other cerebrovascular disease,
simvastatin is prescribed for reducing the risk of mortality by
reducing death from coronary heart disease, reducing nonfatal
myocardial infarction (heart attack)and stroke, and reducing the
need for coronary and noncoronary revascularization
procedures[14].
The drug is in the form of an inactive lactone that is hydrolyzed
after ingestion to produce the active agent. It is a white,
nonhygroscopic,crystalline powder that is practically insoluble in
water, and freely soluble in chloroform,methanol and ethanol.
Usually, patients are started at 20 mg, but the dispersion index
can go from 5 mg to 80 mg a day. If adjustments are required, the
adjustment must be performed at intervals no less than 4 weeks.
The highest approved dose of simvastatin is 80 mg.Common side
effects (>1% incidence) may include abdominal pain, diarrhea,
indigestion, and a general feeling of weakness. Rare side effects
include joint pain, memory loss, and muscle cramps.Cholestatic
hepatitis, hepatic cirrhosis, rhabdomyolysis and myositis have been
reported in patients receiving the drug chronically.
10.C-reactive protein
C-reactive protein (CRP) is a protein found in the blood, the
levels of which rise in response to inflammation (i.e. C-reactive
protein is an acute-phase protein). Its physiological role is to bind
to phosphocholine expressed on the surface of dead or dying cells
(and some types of bacteria) in order to activate the complement
system.Arterial damage results from white blood cell invasion and
inflammation within the wall. CRP is a general marker for