Prescription Drugs

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Prescription Drugs

• FWS 235

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Prescription Drugs

• Must be obtained with physicians direction
• Rx symbol
• Professional supervision
• More powerful than OTCs
• Treat specific disease conditions
• Have more unexpected and adverse effects than
  OTCs

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Prescription Drugs

• Benefit-risk equation
• High probability that absolute safety does not
  exist
• Potential for causing unanticipated and
  unintended drug reactions and experience
  therapeutic effect
• The good (anticipated effects) must outweigh the
  possibility of the bad (unintended or harmful
  side effects)

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Prescriptions and Drug Labels

• Prescription- a physicians order to a pharmacist
  to dispense a specific drug product to a patient
• Labels on prescribed medicines
• Name, address, and phone number of pharmacy
• Prescription number
• Prescribing physicians name

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Prescriptions and Drug Labels

• Date when prescription was filled
• Patients name
• Drug name, especially if a generic drug has been
  substituted
• Directions for use
• controlled substances can not be transferred
  to another person
• Expiration date
• Number of allowable refills

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Prescriptions and Drug Labels

• Controlled drugs are restricted due to the
  Controlled Substances Act
• Schedule I (i.e. heroin)
• Schedule II (prescriptions must be written, not
  phoned in, and not refilled)
• Schedule III IV (prescriptions may be written
  or phoned to a pharmacy, refilled up to five
  times within six months, with refills later)
• Schedule V (prescription and OTC meds with
  approval by pharmacist to 18 and up)

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Using Wisely

• Before using
• Name of med
• When and how often to take the drug
• What the med is supposed to do
• If a new med, can it be taken with others?
• Unwanted side effects that could occur
• What precautions should be taken
• Foods to avoid while using
• Med to be taken until gone or not (antibiotics)

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Using Wisely

• Follow directions on label
• Inform ones physician about medication problems
• If pregnant, consult with physician
• Inform ones physician, surgeon, or dentist about
  medications, if undergoing surgery
• Discard any remaining drugs

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Using Wisely

• Store medications properly
• Do not use outdated medications
• Never give or borrow meds
• Never take meds in dark or from unmarked
  container

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Prescription Drug Classes

• Major categories of drugs share important
  characteristics
• Chemical composition
• Anticipated actions within the body

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Prescription Drug Classes

• Major drug classes
• Analgesics relieve pain and produce insensibility
  to pain
• Anorexics reduce ones appetite
• Anti-alcohol preparations used in management of
  alcoholism
• Aniarthritics are anti-inflammatory action useful
  in treating various joint diseases

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Prescription Drug Classes

• Antihistamines block histamine, and thus prevent
  allergic reactions
• Antiashtmatics relieve breathing difficulties
  associated with bronchial asthma
• Anti-infective drugs inactivate and/or eliminate
  invading, disease-causing microbes
• Antidepressants relive emotional depression

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Prescription Drug Classes

• Antidiabetic agents maintain diabetics blood
  sugar at a nearly normal level, keep the urine as
  free of sugar as possible
• Antidiarrheals manage and control diarrhea
• Antihypertensive drugs used to reduce high blood
  pressure
• Antineoplastics used in treating specific
  cancerous conditions

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Prescription Drug Classes

• Antispasmodics/anti-ulcer agents control various
  disorders of the stomach and intestinal tract
• Cardiovascular drugs affect the function of the
  heart and blood vessels
• Cholesterol-lowering drugs t reduce the amount of
  damaging blood fats
• Diuretics help the body to pass excess water and
  salt and cause a sudden and copious flow of urine

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Prescription Drug Classes

• Diuretics help the body to pass excess water and
  salt and cause a sudden and copious flow of urine
• Sedative-hypnotics induce sleep or produce a
  reduction in tension and anxiety
• Stimulants speed up the function of the CNS

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Prescription Drug Classes

• Tranquilizers
• Major- relieve psychotic symptoms
• Minor- relieve anxiety and reduce tension
• Other classes include
• Anticoagulants (reduce blood clotting)
• Anesthetics (produce loss of sensation)
• Eye and ear preparations
• Hormones (regulate body processes)
• Muscle relaxants
• Narcotic antagonists
• Detoxification agents

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Oral Contraceptives

• Prescription that prevent pregnancy by keeping
  the ovaries from developing and releasing ova,
  blocking ovulation
• Combination oral contraceptive estrogen and
  progestin (99 effective)
• Minipill contains only progestin (97 effective)

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Oral Contraceptives

• Side effects
• Cardiovascular disorders
• Benign tumors of the liver
• Primary liver cancer
• Gallbladder disease
• Hypertension

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Oral Contraceptives

• Non-contraceptive benefits of the pill
• Protective effect against pelvic inflammatory
  disease
• Relief from various menstrual symptoms
• Lessening of premenstrual tension
• Possible protection against ovarian cysts and
  ovarian and uterine cancer, with increased risk
  for breast and cervical cancers

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Oral Contraceptives

• Future of drug-based contraception
• Will never be a perfectly safe contraceptive
• New techniques are being developed
• Depo-Provera
• Subdermal implants (i.e. Norplant)
• LHRH- affects ovulation cycle
• Anti-pregnancy vaccines for women and
  anti-fertility vaccines for men
• Gossypol (suppresses sperm production)

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Oral Contraceptives

• Morning After oral contraception
• Mifepristone (RU-486)- causes shedding of the
  uterus lining and the implanted, fertilized egg
• Other drugs
• Viagra-treats impotence
• Premarin- treats symptoms of menopause
• Evista- prevents bone thinning in post-menopausal
  women
• Meridia- anti-obesity drug

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Side Effects and Adverse Reactions

• Secondary side-effects due to sensitivities,
  allergies, and body chemistry changes
• Minor side-effects include skin rash, mild
  headache, nausea, and drowsiness
• Severe side-effects include prolonged vomiting,
  bleeding, extreme weakness, or impaired vision or
  hearing
• Prolonged use can cause nutritional deficiencies,
  bodys ability to absorb vitamins and minerals

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Therapeutic Index

• Measure that relates the dose of a drug required
  to produce a desirable effect to that dosage
  which produces an undesired effect.
• The higher the ratio, the safer the drug
• LD 50- lethal dose
• ED 50-effective dose

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Preventive Measures

• Informing physician of previous adverse reactions
• Reporting allergic drug reactions to ones
  physician
• Respecting known contraindications (situations
  that would prohibit the use of the drug)
• Exercising precautions in using drugs

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Preventive Measures

• Following prescribed dose recommendations
• Recognizing and reporting early warning signals
  of adverse reactions
• Having ones physician monitor drugs effects

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Polypharmacy

• The use of two or more drugs at the same time
  during the course of treatment for a particular
  illness
• Drug interactions
• Changes in drug absorption, distribution, and
  metabolism
• Alteration of drug excretion
• Independent drug reaction
• Antagonistic drug reaction (drug reduce other
  drug)
• Additive drug reaction (combining two drugs
  effects)
• Potentiation/synergistic drug reaction- an
  exaggerated drug effect, multiplied reaction

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Generic Drugs

• Drug names
• Chemical name describes chemical structure
• Generic name refers to the drugs official name
  that is not patented
• Brand name or trademark (patented) assigned by
  pharmaceutical company which suggests the
  pharmacological action
• Generic drug use is increasing in this country

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Generic Drugs

• Bioavaliability- measure of a drugs activity
  within the body as determined by the measured
  levels of that particular drug in the blood
• Bioequivalence- is the ability of one drug to
  produce the same therapeutic effect in the body
  as an apparently similar medication

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Discussion

• Generics are they a good thing or not?
• Are they as potent as regulatory drugs?
• Do most people feel prescribed drugs are safe?
• Advertising campaigns for prescription drugs do
  you agree or disagree?