Some antibiotics can be prepared from organic sources, such as mold (one type of which is a source of penicillin) or bacteria—for example, this culture of Streptomyces Hvidans.

A physician’s task in treating various kinds of ailments and their symptoms has been made much easier in recent years by the availability of a vast armory of drugs. At the same time, the manufacture of drugs has become a full-scale industry with its own research, testing, packaging, marketing, and promotion divisions. Constant research, refinement, and experimentation by the pharmaceutical companies is continually resulting in the production of new or improved drugs. As an overall consequence, drug treatment is becoming more effective all the time.

Although treatment is undoubtedly improving, drugs are also becoming increasingly expensive, and questions about the cost of producing drugs are of great concern to many people. Research and development is often a long and costly process, and even when a new drug is discovered it can be both difficult and expensive to produce. On the other hand, enormous sums are spent in packaging and advertising drug products, so arguments about costs and waste are difficult to resolve.

One point often used to explain the cost of drugs is that every care must be taken to en sure that they are safe to use. Indeed, it has even been argued that so much attention is paid to safety requirements that this actually inhibits research.

Despite such stringent precautions, however, mistakes do occur, and the question of where responsibility lies is also controversial. Some mistakes are particularly horrifying, as in the cases of malformed children born to women who took the drug thalidomide as a sedative while pregnant. Many drugs are extremely potent agents and most can be dangerous if misused. In any case, drugs should be considered only as temporary solutions even to permanent problems. The fact remains, however, that most drugs are taken on prescription to combat pain or disease, and few are abused.

Thalidomide is a sedative drug used originally in the 1950’s and 1960’s, which caused pregnant women who took it to give birth to physically malformed children. These children were not mentally defective, however, and many live normal lives.

Drugs and the physician

A physician, faced with a patient who has described all the perceived symptoms, may decide to prescribe drug treatment. Most physicians are inundated with leaflets, brochures, and free samples from pharmaceutical companies advertising their drugs, and from these and other sources of information the physician has to choose a drug that provides the maximum help. The treatment might have to be effective in more than one way treating both pain and infection, for example, as well as any other localized or general condition. Alternatively, a combination of drugs might be indicated and the compatibility of the prescribed drugs has to be ensured. For information on this subject, the physician generally consults one of the large reference works on drugs, commonly known as a Physician’s Desk Reference. But a physician may use a “trial and error” approach with certain drugs if the symptoms displayed indicate one of several possible causes.

The physician has also to consider possible side effects of drug treatment. A number of useful drugs have known side effects, and a patient should be warned about these in advance. They can vary from comparatively minor effects, such as the tendency of the painkilling drug codeine to cause constipation, to potentially hazardous ones, such as the drowsiness induced by some drugs prescribed to combat travel sickness. The occurrence of side effects is especially serious in some chemotherapy techniques for treating cancer, in which internal tumors are virtually overwhelmed with drugs. The treatment can be very effective, but there may be visible side effects (such as hair loss) that may depress the patient’s morale. The physician must therefore consider whether such possible side effects balance or even outweigh the potential benefit derived from the use of the drug, and careful monitoring of a patient’s reactions to a drug is therefore essential.

Before contemplating the type of drug to prescribe, the physician must be certain the patient’s condition has been diagnosed correctly. Diagnosis must take into account the patient’s possible inability to explain exactly what and where the symptoms are, the fact that pain can be “referred” from one location in the body to another, and the fact that to a patient a secondary side effect may assume greater importance than that of a primary symptom.

Such analysis requires the physician’s personal knowledge of the patient. And although such a close acquaintance with every patient may be difficult, particularly in an urban area, a physician has to be quite certain before completing a prescription for a drug that the prescribed drug will produce no allergic effects, nor any side effects with which the patient might be unable to cope satisfactorily. A physician has to be especially vigilant in diagnosis when prescribing drugs that could be abused because extended usage of certain drugs could encourage addiction. This is particularly likely with some stimulants and depressants.

Modern surgery relies to a considerable extent on anesthetic drugs and on the skill of the anesthetist to select the appropriate drug and technique of administration, depending on the type of operation and the patient’s age and condition.

The various forms of prescribed drugs

The form in which pharmaceutical compounds are presented solid, liquid, or gaseous depends on the nature of their ingredients and what they are designed to do.

Solid forms include granules, tablets, capsules, and even a type of chewing gum (for weaning smokers off cigarettes). Powders, creams, and ointments are generally designed for external (topical) application. Pessaries and suppositories, which consist of a drug in a soluble base that dissolves in moist conditions and at body temperatures, deliver drugs directly into the vagina and rectum, respectively. Some drugs are designed to be dissolved in water first for easier internal absorption, particularly the proprietary drugs sold as fast-acting painkillers.

Liquid drugs include remedies such as cough mixtures; antibiotic preparations for babies, young children, and elderly people; drugs to counteract gastrointestinal infections; some laxatives; and ulcer-healing preparations. Other liquid drugs are given by injection: under the skin (subcutaneously), into muscle (intramuscularly), or into veins (intravenously). Large volumes of liquid-containing drugs can be administered directly into veins from an intravenous infusion set.

In the latter case, drugs may be prescribed to treat the condition either by eradicating the underlying cause, or by suppressing the symptoms. Usually it is the underlying cause that the physician prescribes the drug to attack, but there are certain conditions (such as peptic ulceration and arteriosclerosis) in which the best treatment is to alleviate the symptoms. There are, in any case, many more symptom-suppressing drugs than there are those that attack root causes.
Moreover, some medical conditions caused by environmental circumstances require treatment with chemicals and substances that are not usually considered drugs. Deficiency diseases, for instance, endemic in some parts of the world, are often only temporarily “cured” by administering proteins, vitamins, or any other substances that make up the deficiency. Proteins and vitamins could then quite legitimately be termed drugs.