Dr. Gbemudu received her B.S. in Biochemistry from Nova Southeastern University, her PharmD degree from University of Maryland, and MBA degree from University of Baltimore. She completed a one year post-doctoral fellowship with Rutgers University and Bristol Myers Squibb.
Jay W. Marks, MD, is a board-certified internist and gastroenterologist. He graduated from Yale University School of Medicine and trained in internal medicine and gastroenterology at UCLA/Cedars-Sinai Medical Center in Los Angeles.
Please Note: Brand name drugs (Quinaglute, Duraquin, Quinact, Quinidex, Cin-Quin,
Quinora) have been discontinued
DRUG CLASS AND MECHANISM: Quinidine is an antiarrhythmic medication that is
used to correct disturbances in the
rhythm of the heart (antiarrhythmic). Other
antiarrhythmic drugs within the same class include procainamide (for example,
Pronestyl) and disopyramide (for example, Norpace). This class of antiarrhythmics is
specifically called "Class I" antiarrhythmics, and they differ from other
antiarrhythmic drugs because they work by interfering with the sodium channel in
the membranes of cells. The sodium channel is part of the membrane (wall)
surrounding every cell that allows sodium to pass through into the cell, making
the cells (for example, muscle and nerve cells) excitable and, in the case of muscle
cells, able to contract. Thus, the flow of sodium through these channels is
necessary for the muscle cells of the heart to be stimulated to contract, and
Class I antiarrhythmics decrease the electrical stimulation of the muscle cells.
There are three actions that are responsible for quinidine's ability to stop
arrhythmias and prevent their recurrence. Quinidine decreases the speed of the
electrical current that travels through the heart muscle that causes the heart
muscle cells to contract. It also prolongs the period during which heart muscle
cells can become electrically stimulated to contract and prolongs the recovery
period after contraction during which the heart muscle cells cannot be
stimulated to contract.
Quinidine blocks the normal effect of the vagus nerve on the heart, causing
an increase in the rate at which the heart beats. Quinidine reduces the force of
contraction of heart muscle cells, and therefore may impair the pumping
efficiency of failing heart muscle as in congestive heart failure. Quinidine
blocks alpha-receptors on the muscle cells that surround arteries which relaxes
the muscle cells, lowers blood pressure ,and can cause excessively
low blood
pressure when combined with other drugs that also relax these muscle cells.
Quinidine was approved by the FDA in July 1950.
PRESCRIPTION: Yes
GENERIC AVAILABLE: Yes
PREPARATIONS:Tablets: 200, 300, and 324 mg. Injections: 800 mg.
STORAGE: Quinidine should be stored at room temperature, 20-25 C (68-77 F).
It should be dispensed in well-closed, light-resistant container.
PRESCRIBED FOR: Quinidine is an antiarrhythmic drug used in the treatment of
abnormal heart rhythms, such as: atrial fibrillation, atrial flutter, and
ventricular arrhythmias such as paroxysmal ventricular tachycardia. Quinidine
also is used to treat malaria.
DOSING:
For adults, the dosage range for quinidine gluconate is from 648 to
2592 mg/day.
For adults, the dosage range for quinidine sulfate is from 400 to
4000 mg/day.
For adults, the dosage range for quinidine gluconate injection is
400 to 2400 mg/day.
DRUG INTERACTIONS: Azole antifungals such as ketoconazole (Nizoral),
fluconazole (Diflucan), itraconazole (Sporanox PulsePak), voriconazole (VFEND),
posaconazole (Noxafil), and protease inhibitor/antiretroviral drugs such as
indinavir (Crixivan), and saquinavir (Invirase) should not be used with
quinidine since their concomitant use can increase quinidine levels by
inhibiting removal of quinidine by the liver. Increased quinidine levels can
increase the risk of quinidine toxicity and cardiac arrhythmias.
Systemic lupus erythematosus is a condition characterized by chronic inflammation of body tissues caused by autoimmune disease. Lupus can cause disease of the skin, heart, lungs, kidneys, joints, and nervous
system. When only the skin is involved, the condition is called discoid lupus.
When internal organs are involved, the condition is called systemic lupus
erythematosus (SLE).
Palpitations are unpleasant sensations of irregular and/or forceful beating of the heart. Palpitations can be relieved in many patients by stress reduction, stopping cigarettes, and reduction of caffeine and alcohol.
Malaria is an infectious disease transmitted by the bite of an infected Anopheles mosquito. Symptoms of malaria include chills, pain, fever, and sweating. Though mild cases of malaria can be treated with oral medication, severe cases require intravenous drug treatment and fluids.
Premature ventricular contractions (PVCs) are premature heartbeats originating from the ventricles of the heart. PVCs are premature because they occur before the regular heartbeat. There are many causes of premature ventricular contractions to include: heart attack, high blood pressure, congestive heart failure, mitral valve prolapse, hypokalemia, hypoxia, medications, excess caffeine, drug abuse, and myocarditis.
Thrombocytopenia refers to a decreased number of platelets in the blood. There are many causes of thrombocytopenia such as decreased platelet production (viral infections for example rubella, mumps, chickenpox, hepatitis C, and HIV); increased platelet destruction or consumption (for example sulfonamide antibiotics, heparin, blood transfusions, and lupus); or increased splenic sequestration (enlarged spleen due to conditions for example liver disease, blood cancers, and more). Treatment of thrombocytopenia depends on the cause.
Heart rhythm disorders vary from minor palpitations, premature atrial contractions (PACs), premature ventricular contractions (PVCs), sinus tachycardia, and sinus brachycardia, to abnormal heart rhythms such as tachycardia, ventricular fibrillation, ventricular flutter, atrial fibrillation, atrial flutter, paroxysmal supraventricular tachycardia (PSVT), Wolf-White-Parkinson syndrome, brachycardia, or heart blocks. Treatment is dependant upon the type of heart rhythm disorder.
Paroxysmal supraventricular tachycardia (PSVT) is an abnormal conduction of electricity in particular areas of the heart. PSVT was referred to at one time as paroxysmal atrial tachycardia or PAT, however, the term PAT is reserved for as specific heart condition. Symptoms of PSVT include weakness, shortness of breath, chest pressure, lightheadedness, and palpitations. PSVT is treated with medications or procedures that return the heart to its normal electrical pattern.
Thrombocytopenia is a lower than normal number of
platelets in the blood.
Platelets are one of the components of the blood along with white and red
blood cells. Platelets play an important role in clotting and bleeding.
Platelets are made in the bone marrow similar to other cells in the blood such
as, white blood cells and red blood cells.
Platelets originate from megakaryocytes which are large cells found in the bone
marrow. The fragments of
these megakaryocytes are platelets that are released into the blood stream. The
circulating platelets make up about two third of the platelets that are released
from the bone marrow. The other one third is typically stored (sequestered) in
the spleen.
Platelets, in general, have a brief 7 to 10 days life in
the blood, after which they are removed from the blood circulation. The number of platelets in
the blood is referred to as the platelet count and is
normally betw...