Syllabus Pharmacology

       Protype drug: Individual drugs that represent groups of drugs are called prototypes. Prototypes, which are often the first drug of a particular group to be developed, are usually the standards with which newer, similar drugs are compared. For example, morphine is the prototype of opioid analgesics; penicillin is the prototype of antibacterial drugs.

SOURCES OF DRUGS

 Drugs are available from varied sources, both natural and synthetic. Drugs were mainly derived from plants (eg, morphine), animals (eg, insulin), and minerals (eg, iron). Now, most drugs are synthetic chemical compounds manufactured in laboratories. Such techniques and other technologic advances have enabled the production of new drugs as well as synthetic versions of many drugs originally derived from plants and animals.

Biotechnology is also an important source of drugs. This process involves manipulating deoxyribonucleic acid (DNA) and ribonucleic acid (RNA) and recombining genes into hybrid molecules that can be inserted into living organisms (Escherichia coli bacteria are often used) and repeatedly reproduced. Each hybrid molecule produces a genetically identical molecule, called a clone. Cloning also allows production of adequate amounts of the drug for therapeutic or research purposes.

Pharmacodynamics

➧ Pharmacodynamics is the process by which a drug works or affects the body.

➧ Drugs may work by replacing a missing body chemical, by stimulating or depressing cellular activity, or by interfering with the functioning of foreign cells.

➧ Drugs are thought to work by reacting with specific receptor sites or by interfering with enzyme systems in the body.

Overview

Pharmacodynamics is the science dealing with interactions between the chemical components of living systems and the foreign chemicals, including drugs, that enter those systems. All living organisms function by a series of complicated, continual chemical reactions. When a new chemical enters the system, multiple changes in and interferences with cell functioning may occur. To avoid such problems, drug development works to provide the most effective and least toxic chemicals for therapeutic use.

Drugs usually work in one of four ways:

1.       To replace or act as substitutes for missing chemicals.

2.       To increase or stimulate certain cellular activities.

3.       To depress or slow cellular activities.

4.       To interfere with the functioning of foreign cells, such as invading microorganisms or neoplasms. (Drugs that act in this way are called chemotherapeutic agents.) Drugs can act in several different ways to achieve these results.

Receptor Sites

Many drugs are thought to act at specific areas on cell membranes called receptor sites. The receptor sites react with certain chemicals to cause an effect within the cell. In many situations, nearby enzymes break down the reacting chemicals and open the receptor site for further stimulation. To better understand this process, think of how a key works in a lock. The specific chemical (the key) approaches a cell membrane and finds a perfect fit (the lock) at a receptor site. The interaction between the chemical and the receptor site affects enzyme systems within the cell. The activated enzyme systems then produce certain effects, such as increased or decreased cellular activity, changes in cell membrane permeability, or alterations in cellular metabolism. Some drugs interact directly with receptor sites to cause the same activity that natural chemicals would cause at that site. These drugs are called agonists. For example, insulin reacts with specific insulin-receptor sites to change cell membrane permeability, thus promoting the movement of glucose into the cell. Other drugs act to prevent the breakdown of natural chemicals that are stimulating the receptor site. For example, monoamine oxidase (MAO) inhibitors block the breakdown of norepinephrine by the enzyme MAO. (Normally, MAO breaks down norepinephrine, removes it from the receptor site, and recycles the components to form new norepinephrine.) The blocking action of MAO inhibitors allows norepinephrine to stay on the receptor site, stimulating the cell longer and leading to prolonged norepinephrine effects. Those effects can be therapeutic (e.g., relieving depression) or adverse (e.g., increasing heart rate and blood pressure). Selective serotonin reuptake inhibitors (SSRIs) work similarly to MAO inhibitors in that they also exert a blocking action. Specifically, they block removal of serotonin from receptor sites. This action leads to prolonged stimulation of certain brain cells, which is thought to provide relief from depression. Some drugs react with receptor sites to block normal stimulation, producing no effect. Curare prevents muscle stimulation, causing paralysis. Curare is said to be a competitive antagonist of acetylcholine. Still other drugs react with specific receptor sites on a cell and, by reacting there, prevent the reaction of another chemical with a different receptor site on that cell. Such drugs are called noncompetitive antagonists.

Drug–Enzyme Interactions

Drugs also can cause their effects by interfering with the enzyme systems that act as catalysts for various chemical reactions. Enzyme systems work in a cascade fashion, with one enzyme activating another, and then that enzyme activating another, until a cellular reaction eventually occurs. If a single step in one of the many enzyme systems is blocked, normal cell function is disrupted. Acetazolamide (Diamox) is a diuretic that blocks the enzyme carbonic anhydrase, which subsequently causes alterations in the hydrogen ion and water exchange system in the kidney, as well as in the eye.

Selective Toxicity

Ideally, all chemotherapeutic agents would act only on enzyme systems that are essential for the life of a pathogen or neoplastic cell and would not affect healthy cells. The ability of a drug to attack only those systems found in foreign cells is known as selective toxicity. Penicillin, an antibiotic used to treat bacterial infections, has selective toxicity. It affects an enzyme system unique to bacteria, causing bacterial cell death without disrupting normal human cell functioning. Unfortunately, most other chemotherapeutic agents also destroy normal human cells, causing many of the adverse effects associated with antipathogen and antineoplastic chemotherapy. Cells that reproduce or are replaced rapidly (e.g., bone marrow cells, gastrointestinal [GI] cells, hair follicles) are more easily affected by these agents. Consequently, the goal of many chemotherapeutic regimens is to deliver a dose that will

be toxic to the invading cells yet cause the least amount of toxicity to the host.

Pharmacokinetics

➧ Pharmacokinetics is the study of how the body deals with a drug.

➧ The concentration of a drug in the body is determined by the balance of absorption, distribution, metabolism, and excretion of the drug.

➧ In determining the amount, route, and appropriate timing of a drug dose, the pharmacokinetics of that drug has to be considered.

Pharmacokinetics involves the study of absorption, distribution, metabolism (biotransformation), and excretion of drugs. In clinical practice, pharmacokinetic considerations include the onset of drug action, drug half-life, timing of the peak effect, duration of drug effects, metabolism or biotransformation of the drug, and the site of excretion. Figure 2.2 outlines these processes, which are described in the following sections.

Critical Concentration

After a drug is administered, its molecules first must be absorbed into the body; then they make their way to the reactive tissues. If a drug is going to work properly on these reactive tissues, and thereby have a therapeutic effect, it must attain a sufficiently high concentration in the body. The amount of a drug that is needed to cause a therapeutic effect is called the critical concentration. Drug evaluation studies determine the critical concentration

required to cause a desired therapeutic effect. The recommended dose of a drug is based on the amount that must be

given to eventually reach the critical concentration. Too much of a drug will produce toxic (poisonous) effects, and too little will not produce the desired therapeutic effects.

Loading Dose

Some drugs may take a prolonged period to reach a critical concentration. If their effects are needed quickly, a loading dose is recommended. Digoxin (Lanoxin)—a drug used to increase the strength of heart contractions—and many of the xanthine bronchodilators (e.g., aminophylline, theophylline) used to treat asthma attacks are often started with a loading dose (a higher dose than that usually used for treatment) to reach the critical concentration. The critical concentration then is maintained by using the recommended dosing schedule.

Dynamic Equilibrium

The actual concentration that a drug reaches in the body results from a dynamic equilibrium involving several processes:

·         Absorption from the site of entry

·         Distribution to the active site

·         Biotransformation (metabolism) in the liver

·         Excretion from the body

These processes are key elements in determining the amount of drug (dose) and the frequency of dose repetition (scheduling) required to achieve the critical concentration for the desired length of time. When administering a drug, the nurse needs to consider the phases of pharmacokinetics so that the drug regimen can be made as effective as possible.

Absorption

To reach reactive tissues, a drug must first make its way into the circulating fluids of the body. Absorption refers to what happens to a drug from the time it is introduced to the body until it reaches the circulating fluids and tissues. Drugs can be absorbed from many different areas in the body: through the GI tract either orally or rectally, through mucous membranes, through the skin, through the lung, or through muscle or subcutaneous tissues.

Routes of Administration

Drug absorption is influenced by the route of administration. Generally, drugs given by the oral route are absorbed more slowly than those given parenterally. Intravenously administered drugs are absorbed the fastest. The oral route is the most frequently used drug administration route in clinical practice. Oral administration is not invasive, and, as a rule, oral administration is less expensive than drug administration by other routes. It is also the safest way to deliver drugs. Oral administration subjects the drug to a number of barriers aimed at destroying ingested foreign chemicals. The acidic environment of the stomach is one of the first barriers to foreign chemicals. The acid breaks down many compounds and inactivates others. This fact is taken into account by pharmaceutical companies when preparing drugs in capsule or tablet form. Certain foods that increase stomach acidity, such as milk products, alcohol, and protein, also speed the breakdown of many drugs. To decrease the effects of this acid barrier and the direct effects of certain foods, oral drugs ideally are to be given 1 hour before or 2 hours after a meal. Some drugs that cannot survive in sufficient quantity when given orally are administered via injection directly into the body. Drugs that are injected intravenously (IV) reach their full strength at the time of injection, avoiding initial breakdown. Basically, these drugs have an immediate onset and are fully absorbed at administration because they directly enter the blood stream. Subcutaneous injections deposit the drug just under the skin, where it is slowly absorbed into circulation. Timing of absorption varies with subcutaneous injection, depending on the fat content of the injection site.

Absorption Processes

Drugs can be absorbed into cells through various processes, which include passive diffusion, active transport, and filtration. Passive diffusion is the major process through which drugs are absorbed into the body. Passive diffusion occurs across a concentration gradient. When there is a greater concentration of drug on one side of a cell membrane, the drug will move through the membrane to the area of lower concentration. This process does not require any cellular energy. It occurs more quickly if the drug molecule is small, is soluble in water and in lipids (cell membranes are made of lipids and proteins), and has no electrical charge that could repel it from the cell membrane. Unlike passive diffusion, active transport is a process that uses energy to actively move a molecule across a cell membrane. The molecule may be large, or it may be moving against a concentration gradient. This process is not very important in the absorption of most drugs, but it is often a very important process in drug excretion in the kidney. Filtration involves movement through pores in the cell membrane, either down a concentration gradient or as a result of the pull of plasma proteins (when pushed by hydrostatic, blood, or osmotic pressure). Filtration is another process the body commonly uses in drug excretion.

Distribution

Distribution involves the movement of a drug to the body’s tissues. As with absorption, factors that can affect distribution include the drug’s lipid solubility and ionization and the perfusion of the reactive tissue. For example, tissue perfusion is a factor in treating a patient with diabetes who has a lower-leg infection and needs antibiotics to destroy the bacteria in the area. In this case, systemic drugs may not be effective because part of the disease process involves changes in the vasculature and decreased blood flow to some areas, particularly the lower limbs. If there is not adequate blood flow to the area, little antibiotic can be delivered to the tissues, and little antibiotic effect will be seen. In the same way, patients in a cold environment may have constricted blood vessels (vasoconstriction) in the extremities, which would prevent blood flow to those areas. The circulating blood would be unable to deliver drugs to those areas, and the patient would receive little therapeutic effect from drugs intended to react with those tissues. Many drugs are bound to proteins and are not lipid soluble. These drugs cannot be distributed to the central nervous system (CNS) because of the effective blood–brain barrier, which is highly selective in allowing lipidsoluble substances to pass into the CNS.

Protein Binding

Most drugs are bound to some extent to proteins in the blood to be carried into circulation. The protein–drug complex is relatively large and cannot enter into capillaries and then into tissues to react. The drug must be freed from the protein’s binding site at the tissues. Some drugs are tightly bound and are released very slowly.

These drugs have a very long duration of action because they are not free to be broken down or excreted. Therefore, they are released very slowly into the reactive tissue. Some drugs are loosely bound; they tend to act quickly and to be excreted quickly. Some drugs compete with each other for protein binding sites, altering effectiveness or causing toxicity when the two drugs are given together.

Blood–Brain Barrier

The blood–brain barrier is a protective system of cellular activity that keeps many things (e.g., foreign invaders, poisons) away from the CNS. Drugs that are highly lipid soluble are more likely to pass through the blood–brain barrier and reach the CNS. Drugs that are not lipid soluble are not able to pass the blood–brain barrier. This is clinically significant in treating a brain infection with antibiotics. Almost all antibiotics are not lipid soluble and cannot cross the blood–brain barrier. Effective antibiotic treatment can occur only when the infection is severe enough to alter the blood–brain barrier and allow antibiotics to cross. Although many drugs can cause adverse CNS effects, these are often the result of indirect drug effects and not the actual reaction of the drug with CNS tissue. For example, alterations in glucose levels and electrolyte changes can interfere with nerve functioning and produce CNS effects such as dizziness, confusion, or changes in thinking ability.

Placenta and Breast Milk

Many drugs readily pass through the placenta and affect the developing fetus in pregnant women. As stated earlier, it is best not to administer any drugs to pregnant women because of the possible risk to the fetus. Drugs should be given only when the benefit clearly outweighs any risk. Many other drugs are secreted into breast milk and therefore have the potential to affect the neonate. Because of this possibility, the nurse must always check the ability of a drug to pass into breast milk when giving a drug to a breast-feeding mother.

Biotransformation (Metabolism)

The body is well prepared to deal with a myriad of foreign chemicals. Enzymes in the liver, in many cells, in the lining of the GI tract, and even circulating in the body detoxify foreign chemicals to protect the fragile homeostasis that keeps the body functioning (Figure 2.2). Almost all of the chemical reactions that the body uses to convert drugs and other chemicals into nontoxic substances are based on a few processes that work to make the chemical less active and more easily excreted from the body. The liver is the most important site of drug metabolism, or biotransformation, the process by which drugs are changed into new, less active chemicals. Think of the liver as a sewage treatment plant. Everything that is absorbed from the GI tract first enters the liver to be “treated.” The liver detoxifies many chemicals and uses others to produce needed enzymes and structures.

First-Pass Effect

Drugs that are taken orally are usually absorbed from the small intestine directly into the portal venous system (the

blood vessels that flow through the liver on their way back to the heart). Aspirin and alcohol are two drugs that are known to be absorbed from the lower end of the stomach. The portal veins deliver these absorbed molecules into the liver, which immediately transforms most of the chemicals delivered to it by a series of liver enzymes. These enzymes break the drug into metabolites, some of which are active and cause effects in the body, and some of which are deactivated and can be readily excreted from the body. As a result, a large percentage of the oral dose is destroyed at this point and never reaches the tissues. This phenomenon is known as the first-pass effect. The portion of the drug that gets through the first-pass effect is delivered to the circulatory system for transport throughout the body. Injected drugs and drugs absorbed from sites other than the GI tract undergo a similar biotransformation when they pass through the liver. Because some of the active drug already has had a chance to reach the reactive tissues before reaching the liver, the injected drug is often more effective at a lower dose than the oral equivalent. Thus, the recommended dose for oral drugs can be considerably higher than the recommended dose for parenteral drugs, taking the first-pass effect into account.

Hepatic Enzyme System

The intracellular structures of the hepatic cells are lined with enzymes packed together in what is called the hepatic microsomal system. Because orally administered drugs enter the liver first, the enzyme systems immediately work on the absorbed drug to biotransform it. As explained earlier, this first-pass effect is responsible for neutralizing most of the drugs that are taken. Phase I biotransformation involves oxidation, reduction, or hydrolysis of the drug via the cytochrome P450 system of enzymes. These enzymes are found in most cells but are especially abundant in the liver. Table 2.2 gives some examples of drugs that induce or inhibit the cytochrome P450 system. Phase II biotransformation usually involves a conjugation reaction that makes the drug more polar and more readily excreted by the kidneys. The presence of a chemical that is metabolized by a particular enzyme system often increases the activity of that enzyme system. This process is referred to as enzyme induction. Only a few basic enzyme systems are responsible for metabolizing most of the chemicals that pass through the liver. Increased activity in an enzyme system speeds the metabolism of the drug that caused the enzyme induction, as well as any other drug that is metabolized via that same enzyme system. This explains why some drugs cannot be taken together effectively:

The presence of one drug speeds the metabolism of others, preventing them from reaching their therapeutic levels.

Some drugs inhibit an enzyme system, making it less effective. As a consequence, any drug that is metabolized by that system will not be broken down for excretion, and the blood levels of that drug will increase, often to toxic levels. These actions also explain why liver disease is often a contraindication or a reason to use caution when administering certain drugs. If the liver is not functioning effectively, the drug will not be metabolized as it should be, and toxic levels could develop rather quickly.

Excretion

Excretion is the removal of a drug from the body. The skin, saliva, lungs, bile, and feces are some of the routes used to excrete drugs. The kidneys, however, play the most important role in drug excretion. Drugs that have been made water soluble in the liver are often readily excreted from the kidney by glomerular filtration—the passage of water and water-soluble components fromthe plasma into the renal tubule. Other drugs are secreted or reabsorbed through the renal tubule by active transport systems. The active transport systems that move the drug into the tubule often do so by exchanging it for acid or bicarbonate molecules. Therefore the acidity of urine can play an important role in drug excretion. This concept is important to remember when trying to clear a drug rapidly from the system or trying

to understand why a drug is being given at the usual dose but is reaching toxic levels in the system. One should always consider the patient’s kidney function and urine acidity before administering a drug. Kidney dysfunction can lead to toxic levels of a drug in the body because the drug cannot be excreted.

Half-Life

The half-life of a drug is the time it takes for the amount of drug in the body to decrease to one half of the peak level it previously achieved. For instance, if a patient takes 20 mg of a drug with a half-life of 2 hours, 10 mg of the drug will remain 2 hours after administration. Two hours later, 5 mg will be left (one half of the previous level); in 2 more hours, only 2.5 mg will remain. This information is important in determining the appropriate timing for a drug dose or determining the duration of a drug’s effect on the body. The absorption rate, the distribution to the tissues, the speed of biotransformation, and how fast a drug is excreted are all taken into consideration when determining the half halflife of the drug. The half-life that is indicated in any drug monograph is the half-life for a healthy person. Using this information, one can estimate the half-life of a drug for a patient with kidney or liver dysfunction (which could prolong the biotransformation and the time required for excretion of a drug), allowing the prescriber to make changes in the dosing schedule. The timing of drug administration is important to achieve the most effective drug therapy. Nurses can use their knowledge of drug half-life to explain the importance of following a schedule of drug administration in the hospital or at home.

Administering Medications

OVERVIEW

Drugs given for therapeutic purposes are called medications. Giving medications to clients is an important nursing responsibility in many health care settings, including ambulatory care, hospitals, long-term care facilities, and clients’ homes. The basic requirements for accurate drug administration are often called the “five rights”: giving the right drug, in the right dose, to the right client, by the right route, at the right time. These “rights” require knowledge of the drugs to be given and the clients who are to receive them as well as specific nursing skills and interventions. When one of these rights is violated, medication errors can occur. Nurses need to recognize circumstances in which errors are likely to occur and intervene to prevent errors and protect clients. This chapter is concerned with safe and accurate medication administration.

 GENERAL PRINCIPLES OF ACCURATE DRUG ADMINISTRATION

1. Follow the “five rights” consistently.

2. Learn essential information about each drug to be given (eg, indications for use, contraindications, therapeutic effects, adverse effects, and any specific instructions about administration).

3. Interpret the prescriber’s order accurately (ie, drug name, dose, frequency of administration). Question the prescriber if any information is unclear or if the drug seems inappropriate for the client’s condition.

4. Read labels of drug containers for the drug name and concentration (usually in mg per tablet, capsule, or milliliter of solution). Many medications are available in different dosage forms and concentrations; it is extremely important that the correct ones be used.

5. Minimize the use of abbreviations for drug names, doses, routes of administration, and times of administration. This promotes safer administration and reduces errors. When abbreviations are used, by prescribers or others, interpret them accurately or question the writers about intended meanings.

6. Calculate doses accurately. Current nursing practice requires few dosage calculations (most are done by pharmacists). However, when they are needed, accuracy is essential. For medications with a narrow safety margin or potentially serious adverse effects, ask a pharmacist or a colleague to do the calculation also and compare the results. This is especially important when calculating children’s dosages.

7. Measure doses accurately. Ask a colleague to doublecheck measurements of insulin and heparin, unusual doses (ie, large or small), and any drugs to be given intravenously.

8. Use the correct procedures and techniques for all routes of administration. For example, use appropriate anatomic landmarks to identify sites for intramuscular (IM) injections, follow the manufacturers’ instructions for preparation and administration of intravenous (IV) medications, and use sterile materials and techniques for injectable and eye medications.

9. Seek information about the client’s medical diagnoses and condition in relation to drug administration (eg, ability to swallow oral medications; allergies or contraindications to ordered drugs; new signs or symptoms that may indicate adverse effects of administered drugs; heart, liver, or kidney disorders that may interfere with the client’s ability to eliminate drugs).

10. Verify the identity of all clients before administering medications; check identification bands on clients who have them (eg, in hospitals or long-term facilities).

11. Omit or delay doses as indicated by the client’s condition; report or record omissions appropriately.

12. Be especially vigilant when giving medications to children because there is a high risk of medication errors. One reason is their great diversity, in age from birth to 18 years and weight from 2–3 kilograms (kg) to 100 kg or more. Another is that most drugs have not been tested in children. A third reason is that many drugs are marketed in dosage forms and concentrations suitable for adults. This often requires dilution, calculation, preparation, and administration of very small doses. A fourth reason is that children have limited sites for administration of IV drugs, and several may be given through the same site. In many cases, the need for small volumes of fluid limits flushing between drugs (which may produce undesirable interactions with other drugs and IV solutions). In 1998, the Food and Drug Administration published a requirement that new drugs likely to be important or frequently used in the treatment of children should be labeled with instructions for safe pediatric use.

ROUTES OF ADMINISTRATION

Routes of administration depend on drug characteristics, client characteristics, and desired responses. The major routes are oral, parenteral, and topical. Each has advantages, disadvantages, indications for use, and specific techniques of administration. The term parenteral refers to any route other than gastrointestinal (enteral), but is commonly used to indicate SC, IM, and IV injections. Injections require special drug preparations, equipment, and techniques. General characteristics are described below; specific considerations for the intravenous route.

Pharmacopoeia

Pharmacopoeia, pharmacopeia, or pharmacopoea, (literally, 'drug-making'), in its modern technical sense, is a book containing directions for the identification of samples and the preparation of compound medicines, and published by the authority of a government or a medical or pharmaceutical society.

Indian Pharmacopoeia Commission (IPC) is an Autonomous Institution of the Ministry of Health and Family Welfare, Govt. of India. IPC is created to set standards of drugs in the country. It’s basic function is to update regularly the standards of drugs commonly required for treatment of diseases prevailing in this region. It publishes official documents for improving Quality of Medicines by way of adding new and updating existing monographs in the form of Indian Pharmacopoeia (IP). It further promotes rational use of  generic medicines by publishing National Formulary of India.

 IP prescribes standards for identity, purity and strength of drugs essentially required from health care perspective of human beings and animals.

IPC also provides IP Reference Substances (IPRS) which act as a finger print for identification of an article under test and its purity as prescribed in IP.

IP standards are authoritative in nature. They are enforced by the Regulatory authorities for quality control of medicines in India. During Quality Assurance and at the time of dispute in the court of law the IP standards are legally acceptable. 

IP is an official document meant for overall Quality Control and Assurance of Pharmaceutical products marketed in India by way of contributing on their safety, efficacy and affordability. The work of the IPC is performed in collaboration with members of the Scientific Body, subject experts as well as with representatives from Central Drugs Standard Control Organization (CDSCO), State Regulatory authorities, specialist from Industries, Associations, Councils and from other Scientific and Academic Institutions.

IP contains a collection of authoritative procedures of analysis and specifications for Drugs. The IP, or any part of it, has got legal status under the Second Schedule of the Drugs & Cosmetics Act, 1940 and Rules 1945 there under.                  

As per the policy of IPC, IP monographs are not framed to detect all possible impurities. The prescribed tests are designed to determine impurities on which attention are required to be focused, to fix the limits of those that  are tolerable to a certain extent, and to indicate methods for ensuring the absence of those, that are undesirable. It is, therefore, not to be presumed that the impurities can be tolerated because they have not been precluded by the prescribed tests.

 Distinction exists between Pharmacopoeial Standards and Manufacturer’s release specifications. Pharmacopoeial standards are publicly-available compliance document that provide the means for an independent check about the quality of a product, all time during its shelf-life. To ensure compliance related to pharmacopoeial requirements, the manufacturer’s specifications may need to be more exacting than corresponding pharmacopoeial specifications.

Legal Notices

In India, under the Drugs and Cosmetics Act 1940, the current edition of Indian Pharmacopoeia is a book of standards for drugs included therein and the standards as included in the Indian Pharmacopoeia would be official. Also, in several other laws of India, the Indian Pharmacopoeia is recognised as the standard book. It is expedient that enquiry be made in each case in order to ensure that the provisions of any such law are being complied with. In general, the Drugs and Cosmetics Act, 1940, the Narcotic Drugs and Psychotropic Substances Act, 1985, the Poisons Act, 1919 and the rules framed thereunder should be consulted. These statutes empower the Government agencies to enforce the law using this compendium. The monographs of the Indian Pharmacopoeia should be read subject to the restriction imposed by those laws which are applicable.

If considered necessary, the standards included in Indian Pharmacopoeia can be amended and the Secretary-cum-Scientific Director is authorised to issue such amendments. Whenever such amendments are issued, the Indian Pharmacopoeia would be deemed to have been amended accordingly.

Patents and Trade Marks

In the Indian Pharmacopoeia, certain drugs and preparations have been included notwithstanding the existence of actual or potential rights in any part of the world. In so far as such substances are protected by Letters Patent their inclusion in the Indian Pharmacopoeia neither conveys, nor implies, licence to manufacture without due permission, authority, or licence from the person or persons in whom such rights exist.

The titles given under the individual monographs are public property. These titles cannot be patented as trade marks and no person is permitted to patent any trade mark devising the root of these titles.

IP Compliance

The interpretation of a monograph must be in accordance with all the general requirements, testing methods, texts and notices pertaining to it, in the IP. A product is not of standard quality unless it complies with all the requirements of the monograph.

Pharmacotherapy