PHAR 100 - Module 5 Flashcards
safety and efficacy of OTC drugs
- all are subjected to preclincal testing for safety
- post-market safety surveillance is also conducted
grandparenting
new regulation don’t apply to products already on the market
guidlines for using an OTC
- illness/symptoms are mild
- use shouldn’t exceed 2 weeks
selection of appropriate OTC
- proven efficacy for the condition
- simplest ingredients
- list of ingredients and their amount
- come in appropriate dosage form
- known level of toxicity
internal analgesics → acetylsalicylic acid (ASA; brand name = Aspirin)
- relieves pain (analgesic), fever (antipyretic), and inflammation (anti-inflammatory)
- ASA inhibits synthesis at prostaglandins, which are endogenous substances that enhance the mediation of pain and fever
- tinnitus (ringing in ears at high doses, bad for children)
- allergic reactions
- gastric irritation (ASA breaks down mucosal barrier in stomach)
internal analgesics → acetaminophen (brand name = Tylenol)
- effective analgesic and antipyretic, not anti-inflammatory
- drug of choice in cases where ASA causes gastric irritation and inferable conditions in children
- inhibition of prostaglandin synthesis
- overdose can lead to fatal liver injury
internal analgesics → non-steroidal, anti-inflammatory agents (NSAIDs) (Ibuprofen - brand name = Advil and naproxen = aleve)
- effective analgesics, antipyretics and anti-inflammatories
- reverse inhibition of the synthesis of prostaglandins
- gastric irritation
topical analgesics
- minor sprains and overworked muscles
- voltarin (an NSAID) has proven efficacy
antihistamines
- treatment of symptoms due to allergy
- block histamine receptors, thereby inhibiting the binding of histamine to its receptor, decreasing allergy symptoms
antacids
- hold the pH of gastric contents at about 4
- neutralize gastric acid by an acid-base reaction
- systemic antacids - given orally and are absorbed by GI tract, leading to systemic alkalosis
- non-systemic antacids - aren’t absorbed and don’t cause systemic alkalosis
decongestants
- cause constriction of blood vessels preventing the accumulation of fluid and thereby reducing congestion
- long-acting preparations are best
cough suppressants
- centrally-acting → block processing of info in the medulla, reducing frequency of the cough; codeine (an opioid)
- peripheral cough suppressant → block the nerve endings in the throat and bronchioles inhibiting the stimulus to cough
expectorants
- reduce the viscosity of the sputum by increasing secretions
- glyceryl guaiacolate
sleeping aids
- main ingredient are an antihistamine that has sedative properties and an analgesic
laxatives
- increases excretion of a soft-formed stool by increasing gut motility or hydration of the stool
- stimulant laxatives → increase motor activity of intestine and increase secretion of mucus, water and electrolytes into the intestine
- bulk-forming laxatives → swell in water to form an emollient gel or viscous solution that serve to maintain soft stool
anti-diarrheal agents
- used to control diarrhea
- main concern with diarrhea is dehydration
- absorbents (Pepto) → add bulk to the GI tract and may absorb toxins
- loperamide → synthetic opioid that doesn’t penetrate into the CNS; inhibits gut motility by acting on opioid receptors in the GI tract, reducing peristaltic activity
0.5% and 1% hydrocortisone
- topical anti-inflammatory used for exposure to poison ivy, insect bits, any anti-inflammatory condition that is treated topically
sunscreens
- contains compounds such as para-aminobenzoic acid derivatives, benzophenone, and cinamic acids
- are absorbed into the outer layer of the skin and scatter UV energy, preventing it from reaching the lower layer of the skin
increase in herbal drugs is due to
- desire of people to use natural products, which they believe are safer than conventional products
- manufacturers and retailers promote these products for financial gain
allopathic medications
drugs used by mainstream medicine; have a DIN number from Health Canada
herbal medications (homeopathics)
plant products sold as medicine (no DIN); often crude mixtures and evaluation is lacking
phytopharmaceuticals
drugs obtained from plants, purified, and used at therapeutic doses with scientific evidence of efficacy and documented toxicity
allopathic phytopharmaceuticals
full status as a drug and meet all requirements of a drug (full safety and efficacy evaluation; DIN)
food supplement
a herbal product that is used at 1/4 of the proposed therapeutic dose
problems associated with herbals
- lack of efficacy and safety data
- lack of standardization
- intentional adulteration (addition of substances other than the herbal)
- questionable source
- drug interactions with allopathic medications
- confusing literature
St. John’s Worts
- treat mild-moderate depression, and to heal wounds
- active ingredients are hypericin and hyperforin
- less effective than other antidepressants
- likely effective for mild to moderate depression
- can cause phototoxicity (sunlight causes a skin reaction)
aloe vera
- applied to skin topically to aid in healing of wounds/burns
- active ingredients are mannans and anthraquinones
- increase in micro-circulation of the skin
- possibly effective for cold sores and minor skin irritations
devil’s claw
- recommended for a wide range of ailments, from migraines to kidney disease
- mainly used for treatment of inflammatory conditions
- active ingredients are glucoirioids
- possibly effective for arthritis and osteoarthritis
ginseng
- enhance memory, learning, productivity, and the immune system
- can also reduce blood sugar in diabetics
- active ingredients are ginsenosides and panaxosides
- possibly effective for thinking and memory, diabetes, erective dysfunction, and COPD
echinacea
- prevention and treatment of the common cold, for wound healing and as an anti-inflammatory agent
- active ingredients are echinacein, cichoric acid and caffeic acid
- can stimulate T-lymphocytes
- possibly effective for the common cold
valerian
- treatment of nervous tension and panic attacks
- active ingredients are valepotriates
- possibly effective for mild insomnia
vitamin
a substance essential for the maintenance of normal metabolic functions, but is generally not made in the body and therefore must be provided from an outside source (except vitamin D and K)
water-soluble vitamins
vitamin C and 11 vitamins in the B group
fat-soluble vitamins
vitamins A, D, E and K
vitamins as supplements
- increased requirements → necessary during growth, pregnancy, breastfeeding
- inadequate intake → bad diet
- disturbance in absorption → prolonged diarrhea, liver disease
nutritional approach to vitamin therapy
- one selects a diet aimed at supplying the RDA for each vitamin, or a multivitamin preparation which supplies the RDA of each vitamin
megavitamin approach to vitamin therapy
- excess water-soluble vitamins are excreted in urine
- high doses of fat-soluble vitamins can accumulate in body fat and can cause severe toxic effects
vitamin A
- found only in animal products
- required for growth and development, normal structure of mucous membranes and epithelial cells
- administered in periods of increased requirement (infancy, pregnancy)
- deficiency can result in delay of growth and development, nigh blindness, dry skin
- excessive intake can result in dry itchy skin, vomiting, headache
vitamin D
- found in meat, fish and mushrooms
- increases absorption of calcium and phosphate from the intestine, regulation of blood calcium level
- used to help prevent osteoporosis
- deficiency can result in decreased absorption of calcium and phosphate from intestine, decreased blood calcium level
- excessive intake can result in elevated calcium levels in blood, excess removal of calcium from bone
vitamin E
- found in vegetable oils and some green leafy veggies
- essential for a number of biochemical reactions, including a role as an antioxidant, and protecting cells in the cardiovascular system
- useful in treatment of premature babies with an uncommon type of hemolytic anemia
- deficiency is rare
- excessive intake can inhibit platelet aggression and contribute to the anticoagulant effects of warfarin
vitamin B12
- found in meat and dairy
- synthesis of RBCs
- absorption decreases as we age → elderly increase intake
- alcohol abuse or malabsorption can lead to deficiencies
folic acid
- all food groups are rich in folate, but fresh greens veggies, liver and yeast are especially high
- synthesis of RBCs
- pregnant women increase intake to prevent neural tube defects
vitamin C
- found in fruits and veggies
- contributes to framework that holds cells together, required for formation on bone and teeth, antioxidant
- prevention and treatment of scurvy
- deficiency can result in scurvy
- excess intake results in diarrhea, formation of kidney stones
food additives
substances that are added to improve the appearance, texture and storage of food
intentional food additives
- substances that are added to improve appearance, texture and storage of food
- vitamins/minerals
- flavours
- colours
- preservatives
unintentional food additives
- substances that are added inadvertently as a result of the growing, manufacturing and storage processes of food
- often termed contaminants
- fertilizers
- pesticides
- heavy metals
safety of food additives
- regulations are more stringent for food additives than OTC drugs
determining toxicity of a food additive
- risk/benefit ratio must be carefully determined
- study toxicity in animals and then extrapolate the results to humans
- limitations are: exposure in humans is hard to replicate in animals, assumption of risk
rational use of food additives
- enhance or maintain quality of food
- should be used inly in quantities sufficient enough to obtain stated ends
- toxicological evaluation of additives should be undertaken
- special groups should be considered
current concerns with food additives
- mistrust of the use of additives
- exposure of children to additives
- natural additives can also be harmful
flavouring
- toxicity’s are rare
- mixtures of artificial flavours
colours
- organic dye added to give food an appetizing appearance
- allergic reactions have occurred
texture agents
- high concentrations found in food
- little to no toxicity
perservatives
- allows the delivery of food to distant destinations and ensures appropriate quality of the food
- benefits outweigh the risks
- antibacterials → smoke, can carry a small carcinogenic risk
- antibiotics → aren’t used in Canada
- sodium nitrate → controversial, added to meat to give
a red colour
- antioxidants → prevent the oxidation and thus rancidity and discolouration of food
- water-soluble → added to reduce oxidation of
carbohydrates (fruit); citric acid - lipid-soluble → prevents fats from oxidizing (chips)
- water-soluble → added to reduce oxidation of
sweeteners
- saccharin - restricted in Canada
- aspartame - replaced saccharin
