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Doxycycline
Doxycycline is the generic name (meaning it is not a
brand name) for a medication that obtained much media
attention in October of 2001 because of its use as a
treament of anthrax, a type of biological infection.
Anthrax is a very dangerous type of bacteria.
Doxycycline is a type of drug that fights off many types
of infections by slowing the growth of bacteria.
Because it can stop the production of bacteria,
doxycycline is used to treat acne.
FEATURED BOOK: Antibiotic Basics for Clinicians
HOW DOES DOXYCYCLINE WORK?
Doxycycline works by stopping the production of protein that the bacteria needs to
survive. Without being able to produce the protein, the bacteria cannot perform essential
functions such as growth and repair. This causes them to eventually stop growing and
die. In treating acne, Doxycycline is thought to slow the production of the bacteria,
Propionibacterium acnes. This bacteria is believed to be important in the formation of
acne.
Doxycycline may also work to treat acne by controlling inflammatory reactions in the
body. Although different people respond to medications at different rates, acne should
respond to Doxycycline by 6 weeks. The normal time frame for acne to respond to
doxycycline is 3 to 6 weeks. In some patients, acne may get worse before it gets better.
"Where Medical Information is Easy to Understand"™
WHAT TYPE OF DRUG IS DOXYCYCLINE?
Doxycycline is a type of drug known as a tetracycline antibacterial.
Antibacterial means that the drug fights bacteria. The word
"tetracycline" refers to the chemical structure of the drug. That is,
drugs that are in the tetracycline class have four 6-membered rings
that make up their basic structure. This makes sense when you
consider that the word "tetra" in Latin means "four," and the word
"cycline" comes from the Greek word, "kyklos," meaning "circle." Put
the two words together and you get "four circles (rings)." Some
tetracyclines occur naturally, whereas others are part natural and
part man-made.
Doxyclyine is part natural and part man-made, which is why it is called a semisynthetic (part man-made)
tetracycline. Specifically, doxycycline is made by changing the chemical makeup of a naturally occurring
tetracycline known as oxytetracycline.
WHAT ARE THE SIDE EFFECTS?
Doxycline has numerous side effects such as photosensitivity (an abnormal sensitivity to light), problems
with the digestive tract (the tube in the body running from the mouth to the anus), and/or the development
of another infection. In children under the age of 8, their teeth may become discolored from using this
drug.
DOES DOXYCYCLINE INTERACT WITH ANY OTHER DRUGS?
Yes. Doxycycline is known to interact with other drugs. You should always contact your doctor to ask if
the particular medications that you are taking interact with doxycycline. Doxycycline is known to interact
with other antibiotics (drugs that fight infections), antiviral drugs (drugs that fight against viruses), and
antacids (drugs that neutralize stomach acids).
Digitalis drugs, which are drugs extracted from plants and used to treat heart conditions, are also known
to interact with doxycycline. Medications taken by mouth that are used to prevent pregnancy can interact
with doxycycline, as can calcium and mineral supplements. Calcium is a type of metallic element that is
important for normal body functioning to take place. Minerals are types of natural substances that are
needed for the body to function properly.
Names of some specific medications that are known to interact with doxycycline are sodium bicarbonate
(an antacid), cefixime (an antibiotic), bismuth salicylate (an antacid and antidiarrhea drug), warfarin (a
drug that prevents blood from clumping together), lithium carbonate (a drug that reduces mania, which is
an abnormal, overly excited state), tiopronin (drugs that prevent kidney stones), etretinate (a drug used to
treat an abnormal skin condition called psoriasis in which red scales are present on the body and covered
with silvery scales), desmopressin (a drug that prevents bleeding and decreases the amount of water that
enters the urine), and cholestyramine (a drug that lowers cholesterol). Cholesterol is a waxy, fatty
substance found in animal tissues.
WHO SHOULD NOT TAKE DOXYCYCLINE?
Not everyone should take Doxycycline, such as people with dysfunction of the liver or kidneys. People
who are hypersensitive to doxycycline or other tetracyclines obviously should not take this drug either.
Pregnant women and children under age 8 are typically not given this drug.
WHAT ELSE IS DOXYCYCLINE CALLED?
Doxycycline has been trademarked (given brand names) by several companies. These names are as
follows: Doxycycline hyclate, Doryx, Doxy-Caps, Doxy-Tabs, Vibramycin, and Vibra-Tabs. By law, the
brand name versions of a generic drug all need to have the same ingredients as the generic version. The
only difference between medications with brand names and those without brand names is the price.
WHY IS IT CALLED DOXYCYCLINE?
The prefix "doxy-" in "doxycycline" refers to the chemical makeup of this drug, which is a-6-Deoxy-5-
hydroxytetra-cycline. So "doxy-" is just a short way of saying "Deoxy." "Cycline" refers to the fact that this
drug is one of the tetracyclines.
