Anti fungal Agents
Various fungi may attack human body
infecting the skin or lungs or indeed other portions of body. One substance
which attacks them particularly is griseofulvin but there are other substances
derived from chemical such as Iso-par, Asterol, Sterisil and sodium Caprylate.
Another are Triacetin and one of the most frequently used is Undecylinic Acid
which is commonly called Desitin.
Antimalarial agents
Malaria
is caused by an organism known as the plasmodium which occurs in various forms
in the body. Quinine and various derivatives of quinine which have been
developed act particularly against the malarial organisms.
Among the important derivatives are
Camoquin, Aralen, Primaquine, Daraprime and Atabrine which were much used
during World War II because these drugs are so powerful they are used only when
prescribed by a physician and in manner prescribed. Drugs may be used to cure
malaria or even taken to prevent malaria.
Antipedicular Agents
Pediculosis is caused by three
varieties of lice, which are commonly called head louse boy louse and they crab
louse. A number of drugs have been developed which are especially active
against lice and these are called pediculocides. These drugs are applied
externally and great care is taken to see that they do not get into the eyes or
on the mucous membranes.
Disinfectants and antiseptics
Among the most important of all disinfectants is chlorine. An ideal
disinfectant has never been discovered because such a substance would have to
have the power to destroy all forms of all infections agents and still not be
injurious in any way to human tissue cells or be capable of causing
sensitization in human beings. Every antiseptic must, therefore, be used in
relationship to its effects not only on the organisims that are to be destroyed
but also on the human body. Various antiseptics and disinfectants depend
principally on chlorine, mercury, silver, peroxides, carbolic acid, soaps, and
similar substances.
Vermifugal Agents
The human being is susceptible to
infestation with a great number of worms, such as the pinworm, the whipworm,
the tapeworm, and hookworm, the filarial, and even such strange worms as the
loa loa. Drugs have now been developed which can rid the body of these worms
but as with the disinfectants and antiseptics, they must be used with great
care because of the danger of toxic reactions.
Anticancer Drugs
Already there are available and in use
under controlled conditions in hospitals a number of drugs which can destroy
the cells of cancer. These are known as cytotoxic agents. Many of them are
highly poisonous and therefore, they must be used only under completely controlled
conditions. Among older drugs which have been used in this way are derivatives
of arsenic and urethane, also nitrogen mustards and substances derived from
folic acid which stop metabolism. X-ray is used to destroy cancer cells and
radioactive isotopes may be used directly in contact with cancer cells. There
are also hormones like estrogens and testosterone which act against the spread
of cancer cells.
Autonomic Drugs
Certain drugs act particularly against
pain in the nerves, against effect of stimuli coming along nerves, and in
tissues of brain. One class of these drug is known as autonomic drugs since
they are concerned with the effects of nerve impulses coming through autonomic
nervous system. This is also known as sympathetic nervous system.
Some drugs induce responses by the
body which mimic the responses which come when stimuli pass laong the nerves of
sympathetic nervous system. One of autonomic drugs is amphetamine or
Benzedrine. This acts to overcome depression. Its effects are opposed to those
of the sedative drugs like the barbiturates. This drug has been found useful in
depressing the appetite and it alleviates sleepiness and fatigue; however, it
is not desirable to eliminate fatigue by destroying the sensation. The real
answer to fatigue is rest. The dangers lie in elimination of warning signal of
fatigue in people who are overdoing. There are also the possibilities of habit
formation from continued use and finally there is possible dangerous effect on
the circulation of the blood.
Other drug of similar type is
Dexedrine, Paredrine, Octin and Isoprel. The number of possibilities is
considerable and perhaps a score of drugs acting in a similar way will
eventually become available.
Some drugs are used to constrict the
membranes of the nose-as adrenalin and Privine. An appetite Ddestroyer is
preludin.
Adrenergic Blocking Agents.
Drugs have been found which can block
the stimuli coming through the sympathetic nervous system. These drugs act to
oppose the action of adrenalin. They lower blood pressure by causing dilation
of the blood vessels and they stimulate the action of the intestines. Usually
they increase the heart rate.
Among the most well known of these
drugs are ergotoxine, erogotamine, piperoxan, and dipenamine.
Cholinergic Agents
These drugs act to produce effects
such as occur when the parasympathetic nerves are stimulated. They can slow the
action of the heart, dilate blood vessels, and increase gastrointestinal motion
and secretion. Most of these drugs are derived from a substance called choline.
Drugs Used for the Heart
Cardiovascular
drugs are those whose action on heart and other portions of blood vessel system
affect either total output of heart or distribution of blood to various
branches of circulation. Some of these drugs affect rhythm and output of heart;
others dilate blood vessels, and still others may act to affect hardening of
the arteries.
Most important of all drugs for heart
is digitalis and associated with it a variety of preparation and derivatives.
Many substances have been discovered
which have a specific effect on high blood pressure. All of these are
potentially toxic and can be used only when prescribed properly by the
physician. One of the best known is hexamethonium, also Apresoline,
mannitolhexanitrate, Inversine, Ansolysen, and Metamine.
Central Nervous System
Many drugs have their principal
actions in depressing the central nervous system. These include anesthetic
drugs, hypnotics, and sedatives. Here also come the anticonvulsants, the drugs
used against cough, and the tranquilizing drugs.
The analgesics are used to relieve
pain. For this purpose morphine is best known, but similar effects are had from
milder salicylates like aaspirin and phenacetin. These mild analgesics do not
produce addiction and are usually considered safe for sale without a
prescription.
The more powerful drugs which have
been developed must be sold only with a prescription.
Many modifications have been made of
opium and its derivatives, including morphine. All of these substances must be
prescribed only with the use of a license to prescribe under the Anti Narcotic
Act.
Many persons have become accustomed to
taking sedative drugs in order to encourage sleep. There are great numbers of
barbituric acid derivatives which are used for this purpose. These are
effective as sedatives and are used in insomnia, hysteria, nervousness, mental
disturbances, and epilepsy. They act directly on the central nervous system.
Insomnia is of several varieties
One in which falling asleep is difficult;
another in which sleep comes easily but is very quickly disturbed so that the
person awakes frequently during the night or exceedingly early in the morning.
Drugs should never be taken routinely for this purpose. Sleep may be promoted
in a variety of ways. Perhaps it is best that sleep-producing drugs be used
only when prescribed and only in the manner of use prescribed and only in the
manner of use prescribed by the doctor. A very small dose of a sleep producing
drug may start sleep and thereafter the person sleeps well throughout the
night.
Many sleep producing drugs are
followed by hangover which seriously interferes with the usual activities.
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