The nature of drugs, drug development and regulation (Katzung, Ch 1. Trans 1-2, wkbk) Flashcards
Deals with the absorption, distribution, and elimination of drugs
Pharmacokinetics
Concerns the actions of the chemical on the organism
Pharmacodynamics
True or False
All substances can under certain circumstances be toxic
True
True or False
The chemicals in botanicals (herbs and plant extracts, “nutraceuticals”) are different from chemicals in manufactured drugs because there is much greater proportion of impurities in manufactured drugs
False
** There is much greater proportion of impurities in botanical drugs
REMEMBER
The molecular size of drugs varies from very small (lithium ion, MW 7) to very large (eg, alteplase [t-PA], a protein of MW 59,050). However, most drugs have molecular weights between 100 and 1000.
The lower limit of this narrow range is probably set by the requirements for specificity of action. The upper limit in molecular weight is determined primarily by the requirement that drugs must be able to move within the body. Drugs much larger than MW 1000 do not diffuse readily between compartments of the body.
**In the case of alteplase, a clot-dissolving enzyme, the drug is administered directly into the vascular compartment by intravenous or intra-arterial infusion.
Three major types of drug-receptor bonds
Covalent, electrostatic and hydrophobic
This type of drug-receptor bond is very strong and in many cases not reversible under biologic conditions
Covalent bond
Example:
- Covalent bond formed between the acetyl group of acetylsalicylic acid (aspirin) and cyclooxygenase, its enzyme target in platelets, is not readily broken
- DNA alkylating agents used in cancer chemotherapy to disrupt cell division in the tumor
True or false
Electrostatic bonding is much more common than covalent bonding in drug-receptor interactions
True
- Electrostatic bonds vary from relatively strong linkages between permanently charged ionic molecules to weaker hydrogen bonds and very weak induced dipole interactions such as van der Waals forces and similar phenomena.
- *Electrostatic bonds are weaker than covalent bonds
This type of bond is important in the interactions of highly lipid-soluble drugs
Hydrophobic
True or False
Drugs that bind through weak bonds to their receptors are generally more selective than drugs that bind by means of very strong bonds.
True
** This is because weak bonds require a very precise fit of the drug to its receptor if an interaction is to occur. Only a few receptor types are likely to provide such a precise fit for a particular drug structure
In the Ra conformation (active form), a receptor can activate downstream mechanisms that produce a small observable effect, even in the absence of drug. This is termed as_______
Constitutive activity
REMEMBER
The receptor is able to assume two conformations. In the Ri conformation, it is inactive and produces no effect, even when combined with a drug molecule. In the Ra conformation, the receptor can activate downstream mechanisms that produce a small observable effect, even in the absence of drug (constitutive activity).
In the absence of drugs, the two isoforms are in equilibrium, and the Ri form is favored.
REMEMBER
The receptor is able to assume two conformations. In the Ri conformation, it is inactive and produces no effect, even when combined with a drug molecule. In the Ra conformation, the receptor can activate downstream mechanisms that produce a small observable effect, even in the absence of drug (constitutive activity).
Conventional full agonist drugs have a much higher affinity for the Ra conformation and mass action thus favors the formation of the Ra–D complex with a much larger observed effect.
REMEMBER
The receptor is able to assume two conformations. In the Ri conformation, it is inactive and produces no effect, even when combined with a drug molecule. In the Ra conformation, the receptor can activate downstream mechanisms that produce a small observable effect, even in the absence of drug (constitutive activity).
Partial agonists have an intermediate affinity for both Ri and Ra forms. Conventional antagonists, according to this hypothesis, have equal affinity for both receptor forms and maintain the same level of constitutive activity.
REMEMBER
The receptor is able to assume two conformations. In the Ri conformation, it is inactive and produces no effect, even when combined with a drug molecule. In the Ra conformation, the receptor can activate downstream mechanisms that produce a small observable effect, even in the absence of drug (constitutive activity).
Inverse agonists, have a much higher affinity for the Ri form, reduce constitutive activity, and may produce a contrasting physiologic result.
Binding of a drug to a nonregulatory molecule such as plasma albumin will result in no detectable change in the function of the biologic system, so this endogenous molecule can be called _____
Inert binding site
** Such binding is not completely without significance, however, because it affects the distribution of drug within the body and determines the amount of free drug in the circulation. Both of these factors are of pharmacokinetic importance
A weak acid is best defined as a neutral molecule that can reversibly dissociate into an anion (a negatively charged molecule) and a proton (a hydrogen ion)
A weak base can be defined as a neutral molecule that can form a cation (a positively charged molecule) by combining with a proton
REMEMBER
The protonated form of a weak acid is the neutral, more lipid-soluble form, whereas the unprotonated form of a weak base is the neutral form
Inspection confirms that the lower the pH relative to the pKa, the greater will be the fraction of drug in the protonated form. Because the uncharged form is the more lipid-soluble, more of a weak acid will be in the lipid soluble form at acid pH, whereas more of a basic drug will be in the lipid-soluble form at alkaline pH
REMEMBER
Almost all drugs are filtered at the glomerulus. If a drug is in a lipid-soluble form during its passage down the renal tubule, a significant fraction will be reabsorbed by simple passive diffusion
If the goal is to accelerate excretion of the drug (eg, in a case of drug overdose), it is important to prevent its reabsorption from the tubule. This can often be accomplished by adjusting urine pH to make certain that most of the drug is in the ionized state. Thus, weak acids are usually excreted faster in alkaline urine; weak bases are usually excreted faster in acidic urine
An inactive precursor chemical that is readily absorbed and distributed which must be converted to the active drug by biologic processes inside the body
Prodrug
For a drug given orally to produce an effect in the central nervous system, it must pass through barriers that include the tissues that make up the wall of the intestine, the walls of the capillaries that perfuse the gut, and the blood-brain barrier, the walls of the capillaries that perfuse the brain
Therefore drugs that enter the CNS must be lipid-soluble
Aqueous diffusion of drug molecules is usually driven by the concentration gradient of the permeating drug, a downhill movement described by Fick’s law. Drug molecules that are bound to large plasma proteins (eg, albumin) do not permeate most vascular aqueous pores.
If the drug is charged, its flux is also influenced by electrical fields (eg, the membrane potential and—in parts of the nephron—the transtubular potential)
This property of drug determines how readily the molecule moves between aqueous and lipid media
Lipid-aqueous partition coefficient
- *In the case of weak acids and weak bases (which gain or lose electrical charge-bearing protons, depending on the pH), the ability to move from aqueous to lipid or vice versa varies with the pH of the medium, because charged molecules attract water molecules.
- *The ratio of lipid-soluble form to water-soluble form for a weak acid or weak base is expressed by the Henderson-Hasselbalch equation
Before clinical testing:
(1) Identification or elucidation of a new drug target
(2) Rational design of a new molecule based on an understanding of biologic mechanisms and drug receptor structure
(3) Screening for biologic activity of large numbers of natural products, banks of previously discovered chemical entities, or large libraries of peptides, nucleic acids, and other organic molecules
**Steps (1) and (2) are often carried out in academic research laboratories
This phase of drug development involves a variety of assays at the molecular, cellular, organ system, and whole animal levels to define the pharmacologic profile, i.e., the activity and selectivity of the drug. The type and number of initial screening tests depend on the pharmacologic and therapeutic goal
Preclinical trial – drug screening
**The desired result of this screening procedure (which may have to be repeated several times with congeners of the original molecule) is a lead compound
In this phase of CLINICAL TRIAL, the effects of the drug as a function of dosage are established in a small number (20–100) of healthy volunteers. If the drug is expected to have significant toxicity, as may be the case in cancer and AIDS therapy, volunteer patients with the disease participate rather than normal volunteers
Phase 1
REMEMBER
Phase 1 trials are done to determine the probable limits of the safe clinical dosage range. These trials may be nonblind or “open”; that is, both the investigators and the subjects know what is being given.
Alternatively, they may be “blinded” and placebo controlled. Pharmacokinetic measurements of absorption, half-life, and metabolism are often done. Phase 1 studies are usually performed in research centers by specially trained clinical pharmacologists
In this phase of CLINICAL TRIAL, the drug is studied in patients with the target disease to determine its efficacy (“proof of concept”), and the doses to be used in any follow-on trials. A modest number of patients (100–200) are studied in detail. A single-blind design may be used, with an inert placebo medication and an established active drug (positive control) in addition to the investigational agent.
Phase 2
**Phase 2 trials are usually done in special clinical centers (eg, university hospitals). Phase 2 trials have the highest rate of drug failures, and only 25% of innovative drugs move on to phase 3
In this phase of CLINICAL TRIAL, the drug is evaluated in much larger numbers of patients with the target disease usually thousands to further establish and confirm safety and efficacy.
Phase 3
**Using information gathered in phases 1 and 2, phase 3 trials are designed to minimize errors caused by placebo effects, variable course of the disease, etc. Therefore, double-blind and crossover techniques are often used. Phase 3 trials are usually performed in settings similar to those anticipated for the ultimate use of the drug.
This phase constitutes monitoring the safety of the new drug under actual conditions of use in large numbers of patients
Phase 4
Philippine FDA-registered herbal medicines
Lagundi – Vitex negundo L; used as an anti-histaminic (anti-asthmatic, expectorant and anti-inflammatory)
Sambong – Blumea balsamifera; used in urinary tract pain and burning, to increase urinary output in edema, or as a preparation before laser treatment of kidney or bladder stones
Akapulko – Cassia alata L; used as an antifungal, anti-lice and; anti-scabies
Tsaang gubat – Carmona retusa (Vahl) Masam; used in acute diarrhea, biliary colic and; gastric/intestinal colic from acute gastroenteritis
Yerba buena – Menthacordifolia opiz; used in the symptomatic relief of mild to moderate pain secondary to circumcision, episiotomy, skin biopsy and; dental extractions
Cardinal Concepts in Pharmacology
- No drug can create a new effect
- At most a drug can modulate intrinsic physiologic function
- Can potentially alter the rate at which a bodily function proceeds
Refers to the percentage of an active drug in a drug product that enters the systemic circulation at a certain rate
Bioavailability
It is a measure of whether the bioavailability (BA) of a certain drug product is closely similar to the BA of the indicator drug
Bioequivalence
Sources of drugs
- plant sources
- animal sources
- microbes
- Earth/soil
- human sources
PLANT SOURCES
a. Alkaloids
b. Glycosides
c. Oils
d. Gum
e. Resin: rosin-like substance usually formed by the oxidation of volatile oils; most are used as cathartics (pine rosin)
f. Tannins: complex principle found widely distributed in plants; has astringent action and is used in the treatment of burns, diarrhea and hemorrhoids (tannic acid)
PLANT SOURCES
Alkaloids – basic organic substances containing carbon, hydrogen, nitrogen, and oxygen; occurs in almost all parts of plants but are most often found in seeds, roots and leaves
Atropine [anti-muscarinic] Vinblastine Vincristine [anti-cancer] Quinine [anti-malaria] Quinidine Reserpine Scopolamine Cocaine Ephedrine Caffeine Colchicine [anti-gout] Morphine [analgesia] Theophylline [treatment for asthma] Theobromine
PLANT SOURCES
Glycosides – ether-like combinations of sugar with some other organic substances
Digoxin [for congestive heart failure] Digitoxin Coumarin [anticoagulant] Salicin [anti-inflammatory] Hesperidin Rutin Quercetin
PLANT SOURCES Oils 1. Volatile oil: evaporates readily without leaving a stain o Peppermint [anti-septic] o Oil of thyme o Spearmint o Oil of winter green
- Fixed oil: greasy substance that leaves a stain
o Castor [laxative]
o Olive oil
PLANT SOURCES
Gum – secretory products from plants; carbohydrates that absorbs water and swell to form thick mucilaginous colloid solutions [used as external agent]
Gum acacia
Emulsifying agents
Drugs from plant sources and their uses LEAF PLANT: DRUG: USE:
Drugs from plant sources and their uses LEAF PLANT: Digitalis DRUG: Digoxin USE: CHF
Drugs from plant sources and their uses BARK PLANT: DRUG: USE:
Drugs from plant sources and their uses BARK PLANT: Cinchona DRUG: Quinine USE: Malaria
Drugs from plant sources and their uses FRUIT PLANT: DRUG: USE:
Drugs from plant sources and their uses FRUIT PLANT: Opium poppy DRUG: Morphine USE: Analgesic
Drugs from plant sources and their uses SEED PLANT: DRUG: USE:
Drugs from plant sources and their uses SEED PLANT: Calabar bean DRUG: Eserine/physostigmine USE: Glaucoma
ANIMAL SOURCES
Insulin
Protamine [antagonist of heparin]
Thyroid
Drugs from animal sources and their uses COW ORGAN: DRUG: USE:
Drugs from animal sources and their uses COW ORGAN: Pancreas DRUG: Insulin USE: DM
Drugs from animal sources and their uses FISH ORGAN: DRUG: USE:
Drugs from animal sources and their uses FISH ORGAN: Sperm DRUG: Protamine USE: Neutralize heparin effect
Drugs from animal sources and their uses PIG ORGAN: DRUG: USE:
Drugs from animal sources and their uses PIG ORGAN: Intestine DRUG: Heparin USE: Anticoagulant
Drugs from animal sources and their uses OX ORGAN: DRUG: USE:
Drugs from animal sources and their uses OX ORGAN: Thyroid DRUG: Dessicated thyroid USE: Hypothyroidism
Sources of drugs
MICROBES
Penicillium Beta-lactam Gentamicin Streptomyces Bacitracin
Drugs from microbes and their uses
SOURCE:ANTIBIOTIC:USE
PENICILLIUM: Penicillin: Broad spectrum; Gm +
CEPHALOSPORIUM: Cefalexin: Broad spectrum; Gm +
MICROMONOSPORA: Gentamicin: Gm -
STRETOMYCES VENEZUELACE: Chloramphenicol: Broad spectrum
STREPTOMYCES GRISEUS: Streptomycin: TB
BACILLUS SUBTILIS: Bacitracin: Gm +
Drugs from minerals and their uses
MINERAL:USE
IRON (Ferrous sulfate): Iron deficiency anemia
SODIUM (Sodium chloride): Dehydration; electrolyte imbalance
IODINE (Potassium iodide): Endemic goiter
MAGNESIUM (Magnesium sulfate): Purgative; tocolytic
BICARBONATE (Sodium bicarbonate): Antacid
ALUMINUM (Aluminum hydroxide): Antacid
Drugs from human sources and their uses.
MEDICATION:USE
HUMAN CHORIONIC GONADOTROPIN: Tumor marker; infertility
REGULAR INSULIN: DM
UROKINASE: Thrombolytic agent
SYNTHETIC DRUG - There is no need for a natural source - Pure chemical substances produced in the laboratory, made by emulating or imitating substances found in nature. Advantages: 1. Better quality control 2. Process is easy and cheap 3. More potent and safer alternatives 4. Large scale production Examples: 1. Co-trimoxazole 2. Diphenoxylate 3. Meperidine 4. Ofloxacin
SEMI-SYNTHETIC DRUG - A natural chemical compound is modified in the laboratory - Examples: Morphine: hydrocodone Penicillin: amoxicillin Caphalosporin C: cefalexin Salicin: aspirin
Things to consider when manufacturing a drug for commercial use:
o Stability
- Drug should be stable (temperature, pH, wont disintegrate immediately, etc)
o Shelf life
- Higher shelf-life, lower price (since the need for production won’t be immediate)
o Pharmacokinetic factors
- Influence of the body to the drug
o Patient factors:
- Child: ex. how to initiate administration of the drug
- Liquid drops (infants)
- Suspension (children)
- Capsule (mainly for adults)
EXCIPIENTS FUNCTIONS
- To maintain stability
- To prolong shelf life
- In consideration of pharmacokinetic factors
- Addressing patient factors
EXCIPIENTS FUNCTIONS:
To maintain stability
- Fillers
Add volume; usually inert (no reaction when mixed with the pharmacologic ingredient)
Should be compatible with other components; cheap
Tasteless or pleasant taste - Binders
Keep ingredients in a tablet together (especially in solids/tablets)
Ensure that tablets and granules can be formed with required mechanical strength, and gives volume to low active dose tablets (e.g. saccharides, sorbitol, gelatin, PEG) - Lubricants
Prevents ingredients from clumping together and sticking to the tablet punches or capsule filling machine - Sorbents
Used for tablet or capsule moisture-proofing by limited fluid sorbing in a dry state
REMEMBER
Role of a lubricant:
True lubricant role:
o Decrease friction at the interface between a tablet’s surface and the die wall during ejection and reduce wear on punches and diesAnti-adherent role:
o Prevent sticking to punch faces or in the case of encapsulation, lubricants. Prevents sticking to machine dosators, tamping pins
Glident role:
o Enhance product flow by reducing interparticulate friction
EXCIPIENTS FUNCTIONS:
To prolong shelf life
- Preservatives
Vitamins A, C, E, selenium, cysteine, methionine, citric acid, Na citrate - Coating agent
Serve to protect tablets from destruction in the environment, heat from the sun; (e.g. HMPC, hydropropylcellulose, and methylcellulose) - Humectant
Attracts and retain moisture drawing water vapor and reduce rate of moisture loss (e.g. calcium chloride, sodium lactate, glycerin, mannitol, sorbitol, PEG)
EXCIPIENTS FUNCTIONS:
In consideration of pharmacokinetic factors
- Coating agent
- Solvent
- Buffer agents
- Surfactants
- Disintegrants
EXCIPIENTS FUNCTIONS:
Addressing patient factors
- Colors
Easy identification of medication
Adds to the identification of the tablet
In children, it appeals to the attractiveness
Viagra is blue (“the blue pill”) - Flavors/sweetness
Bitter: mint/cherry
Salty: peach, apricot
Sour: raspberry
Pinoy flavors: banana (like pedialight), dalandan
Solid dosage requirements: o Should not have difficulty in swallowing o Old enough to swallow o Conscious o No abnormalities in GIT o Drug can be absorbed in the GIT
Different Solid Preparations:
- Tablets
- Capsules
- Lozenges or Pastilles
- Plaster
- Pills
- Spansules - Capsule containing granules with coating to slowly disintegrate the drug
Different Solid Preparations:
Tablets
Granulated or powdered drugs which are compressed or molded into round, discoid, or ovoid shapes
a. Uncoated tablet
b. Multilayered tablet
c. Scored tablet
d. Coated tablets
e. Sustained release tablets
f. Suppository
Different Solid Preparations:
Tablets - Uncoated tablet
Fast dissolution Compressed tablet like Biogesic, aspirin Sublingual and buccal tablets Effervescent tablets It readily disintegrates in the mouth Chewable tablets (e.g. Aspilets) Lozenges, troches
Different Solid Preparations:
Tablets - Multilayered tablet
Ex.: Alaxan, which contains paracetamol and ibuprofen
Different Solid Preparations:
Tablets - Scored tablet
Example: Tablets for hypertensive patients.
Scores used for dividing
Must have good storage to avoid oxidation; oxidation lessens the efficacy of the drug.
Different Solid Preparations:
Tablets - Coated tablets
Enteric, sugar coated; also called a caplet
Example: Viagra
Cannot be divided because oxidation reaction and other reactions can affect the drug.
Sugar coating to cover drugs’ bitter taste
Different Solid Preparations: Tablets
Sustained release tablets
Ensure compliance, i.e. take in once a day rather than thrice a day
Suppository
Tablets inserted in cavities
Mixture of substances with a firm base suitable for insertion into body cavities
Disintegrates in a fast rate
Ex. vaginal suppository - makes use of a dispenser; rectal suppository
**Rectal route acts faster than the oral route since it doesn’t pass through the first part of metabolism
Different Solid Preparations:
Capsules
Soluble container made of tasteless gelatin containing powdered or liquid drugs
a. Hard shell capsule
Contains solids like powder or granules
When a capsule is taken only once a day it most likely contains granules
b. Soft shell capsules
Contains active ingredient mixed with oil
Example: Vit. E and omega 3
Advantages and disadvantages of tablets:
ADVANTAGES
1. Can make the drug more palatable; address taste and odor concerns
2. May contain larger amounts of ingredients (more than 500mg)
3. Easy product identification
4. Can make the drug more palatable; address taste and odor concerns
5. Can house multiple ingredients (eg. Alaxan)
6. Can make numerous sustained release preparations
7. For large scale production
8. Can prolong shelf life
DISADVANTAGES
- Hard to swallow (large tablets)
- Some drugs have poor solubility
- Need a machine to produce large quantities
- Needs multiple excipients
- Some drugs resist compression
HARD SHELL CAPSULES
- ADVANTAGES
1. Rapid drug release
2. Comes in all shapes
3. Easy to manufacture
4. Good oxygen barriers - DISADVANTAGES
1. Slow filling equipment
2. Sticks together
3. Made out of bones of animals (chitosan)
SOFT SHEL CAPSULES
- ADVANTAGES
1. Easy to swallow
2. Comes in all shapes
3. Taken in various ways
4. Tamper resistant - DISADVANTAGES
1. Costly
2. Sticks together
3. Made out of skin of pigs
LIQUID DOSAGE Different liquid preparations 1. Aqueous solutions a. solution b. aromatic water c. syrup d. douche e. enemas f. gargles g. nasala solution h. mucilage i. decoction j. infusion
- alcoholic preparations
a. elixir
b. spirit of essence
c. tincture - Emulsion
- Suspension
a. Mixture/oral suspension
b. magmas and milk
c lotion - extractives
a. tincture
b. extract
c. fluid extract
Different liquid preparations: Solution
homogenous liquid prepared by dissolving a solid, liquid, or gas in water
o Strong iodine solution
o Saturated solution of potassium iodide
Different liquid preparations: Infusion
less active ingredient than extracts;
obtained by extracting the active principle of a substance by using cold or hot water
Different liquid preparations: Decoction
obtained by boiling medicinal herbs in water
has more of the active ingredient than infusions, but less than extracts
Different liquid preparations: Gargles
for cleansing;
used for treating the pharynx and nasopharynx by forcing in from the lungs through the gargle which is held in the throat
Different liquid preparations: Douche
for cleansing part of a body cavity
Different liquid preparations: Enema
preparation done prior to colonoscopy/surgery
rectal injections employed to evacuate the bowel
Different liquid preparations: Spirits
alcoholic or hydroalcoholic solutions of volatile substances
Different liquid preparations:Emulsion
Two immiscible liquids in which one liquid is dispersed in the form of small droplets throughout another liquid
ex. Vitamins are Oil in water emulsion
Different liquid preparations: Suspension
Won’t dissolve into homogenous solution;
preparations of finely divided drugs suspended in water by means of agents
Will need to hake to ensure equal doses of active ingredients
Different liquid preparations:Extracts
a lot of the active ingredient since it is more concentrated
Different liquid preparations: Syrups
heavily mixed with sugars;
concentrated solution of sugar in water
Different liquid preparations: Elixir
also heavily mixed with sugars
hydroalcoholic solution intended for oral use
eg benadryl
Advatages and disadvantages of liquid forms
- ADVANTAGES
1. Easy to swallow
2. Faster absorption
3. Flexibility in proper dosing, i.e. ability to adjust dosage
4. Faster dissolution rate
- DISADVANTAGES
1. Shorter shelf life
2. Difficult to administer
3. Might need special storage
4. Harder to measure
SEMISOLID DOSAGE
Properties
o Smooth texture
o Homogenous
o Non-dehydrating, non-greasy, non-staining, non-irritating
o Do not alter membrane function: Some topical agents can dry up the skin and cause breaks due to some of the ingredients
o Miscible with skin secretions
o Can easily be applied with efficient drug release
o High aqueous washability
Role of Semi-solids o Emollient - Sooths the skin, prevents dehydration without evaporation of the ingredients, with good moisturizing quality o Occlusive - Applied to burned areas to protect the exposed dermal tissues, muscles, and bones o Lubrication - True with topical eye gels o Application of active ingredient
Different forms of semi-solids
- Ointment
- Cream
- Paste
- Gel
Different forms of semi-solids: Ointment
Homogenous, translucent, viscous semi-solid greasy preparation applied to the skin or the mucous membrane
Main function is to apply the active ingredient (drug delivery)
Secondary role s to sooth the surface and maintains hydration
Most of the topical antibiotics are in the ointment form
Ex.: Teramycin to the wound
Different forms of semi-solids: Cream
Viscous, opaque emulsion
Consistency depends on emulsion:
Water in oil: lipophilic material and moisturizes and hydrates skin (ex. Moisturizers); good as emollient and cleansing agent
Oil in water: hydrophilic form and good for drug delivery (ex. Antibiotics); does not easily attract dirt
Different forms of semi-solids: Paste
Contains high percentage of insoluble solids, are therefore highly concentrated
Ointment-like preparation consisting of an absorptive powder dispersed in petrolatum; used in treatment of oozing lesions
Less greasy, good adhesion to the skin
For drug delivery
Ex: zinc oxide
Different forms of semi-solids:Gel
Hydro-alcoholic polymeric matrix with high degree of chemical and physical cross-linking
Semisolid homogenous preparation in which a substance is distributed uniformly throughout the liquid
Hydrated Forms of soluble drugs are in gel form
Main function is to lubricate and maintain hydration
PARENTERAL DOSAGE
Drugs that are being used for injection or infusion into the blood stream, through the use of syringe and needle
Routes: IV, IM, SQ
Different forms of parenterals:
- Ampule - Contains liquid, in a form of aqueous solution
- Vial - Solid form inside, need a solvent
DRUGS FOR INHALATION
Inhaler
Powder, granule, solutions, emulsion or suspensions in a mixture held under pressure in a dispenser
Salbutamol for asthma
Nebulizer
Device used to administer medication in the airways through vapour formed from the release of air or oxygen from the machine into the cavity where there is the liquid form of the drug, which is then inhaled by the patient
Dangerous drugs
- Prohibited drugs
2. Regulated drugs
Dangerous drugs: Prohibited drugs
- Narcotic drugs - drugs that relieve pain, induce sleep and produce withdrawal symptoms when stopped after chronic administration; e.g. opium, morphine, heroine, codeine, meperdine and methadone
- Stimulants - produce mental and physical stimulation, euphoria and self-satisfaction; e.g. cocaine, alpha and beta eucaine
- Hallucinogens - provoke alterations of time and space perception, illusions and delusions; e.g marijuana, LSD, mescaline
Dangerous drugs: Regulated drugs
- include self-inducing sedatives, such as secobarbital, phenobarbital and any drug which contains a salt or a derivative of a salt of barbituric acid; any salt, isomer or salt of an isomer of amphetamine; and hypnotic drugs
DANGEROUS DRUG PREPARATIONS (DDP): SPECIFIC PRESCRIPTION REQUIREMENTS
Per DDB Regulation No, 3 s. 2003 - to be prescribed thru DOH Official Rx Form, 1 DDP per Rx, partial filling allowed, No Refill
A. Buprenorphine (Norspan patch) B. Codeine as poly styrene divinyl benzene sulfonate (Codipront N Capsule; Codipront N Syrup) C. Diazepam (Ampul: anxiol, diazepam, lorcam, trankil, valuim) D. Ephedrine sulfate E. Fentanyl F. Fentanyl citrate G. Hydromorphone Hydrochloride (jurnista tablet) H. Methylphenidate I. Midazolam J. Morphine Sulfate K. Oxycodone Hydrochloride L. Pethidine Hydrochloride M. Phenobarbital sodium N. Pentobarbital sodiun
DANGEROUS DRUG PREPARATIONS (DDP): SPECIFIC PRESCRIPTION REQUIREMENTS
Per DDB Regulation No, 3 s. 2005 - to be prescribed thru Ordinary Rx with S2, 1 DDP per Rx, partial filling allowed, No Refill
Ketamine ( vial: ketamax, ketozol, ketram)
DANGEROUS DRUG PREPARATIONS (DDP): SPECIFIC PRESCRIPTION REQUIREMENTS
Per DDB Regulation No, 4 s. 2005 - preparation not in injectable form i.e. capsule, tablet or syrup, to be prescribed thru Ordinary Rx with S2, 1 DDP per Rx, partial filling allowed, No Refill
A. Pseudoephidrine Hydrochloride
B. Pseudoephidrine Sulfate
DANGEROUS DRUG PREPARATIONS (DDP): SPECIFIC PRESCRIPTION REQUIREMENTS
Per DDB Regulation No, 8 s. 2004 - preparation not in injectable form i.e. capsule, tablet or syrup, to be prescribed thru Ordinary Rx with S2, 1 DDP per Rx, partial filling allowed, No Refill
A. Diazepam B. Bromazepam C. Clonazepam D. Chlorazepate dipotassium E. Estazolam G. Flurazepam H. Mazindol I. Midazolam J. Nitrazepam K. Phenobarbital sodium L. Phentermine Resin M. Zolpidem
Selected latin abbreviations and meanings Abbreviation:derivation:meaning ac: ante cebum: before meals bid: bis in die: 2x a day g: gramma: gram gr: granum: grain gtt: gutta: a drop h: hora: hour hs: hora somni: at bedtime non rep: non repetatur: not to be repeated pc: post cebum: after meals prn: pre re nata: when needed qh or q1h: quaque hora: every hour qid: quator in die: 4x a day qs: quantum sufficit: sufficient quantity Sig or S: signa: laberl stat: statum: immediately tid: ter in die: 3x a day
Metric doses and apothecary equivalents Metric: appox apothecary equiv 30 ml: 1 fluid ounce 60 mg: 1 grain 30 g: 1 ounce
Approximate equiv of household measures 1 drop: 1/20 ml: 1 minim 1 teaspoonful: 8 ml: 1 dram 1 tablespoon: 15 ml: 1/2 fluid ounce 1 glassful: 250 ml: 8 fluid ounces
