Endocrine Flashcards
what causes diabetes
- decrease in insulin secretion with or without a reduction in insulin action -> elevated levels of blood glucose
- insulin does not function properly or not produced in efficient amounts -> not take up the glucose into the cells -> glucose remains in the blood -> hyperglycaemia
what are normal blood sugar levels when a patient is fasting
- between 4.0 and 6.0 mol/L
- 2 hours post meals 5.0-8.0 mmol/L
- normal HbA1C is <6.0%
where is insulin made and secreted
- by the beta cells of the islets of langerhans in the pancreas
what is type 1 diabetes and what are its s&s
- absolute insulin deficiency as a result of destruction of pancreatic islet beta cells
- autoimmune process whereby insulin antibodies in the body are involved in pancreatic cell destruction
- characterized by drowsiness, nausea, sweating, tachycardia and coma
- onset of symptoms quick
what is type 2 diabetes
- insulin resistance
- adequate, near adequate or perhaps even excessive amounts of insulin
- genetic disposition (heredity) plays a major role in development
- usually obese and symptoms are gradual
what are complications of diabetes
- microvascular: eye (retinopathy), gingiva, kidney, nerves (Neuropathy) and extremities
- macrovascular: Coronary Artery Disease (major cause of death in diabetics), Congestive Heart Disease, peripheral vascular disease, hyperlipidemia, hypertension
- periodontal disease
what is HbA1c
- measures the percentage of hemoglobin in the red blood cells that is bound to glucose
- reflect mean blood glucose concentrations over the preceding 2-3 months
- the goal is to have a HbA1c of 7% or lower in diabetics, and 6% in non diabetics
how do we diagnose and treat diabetes
- random blood glucose between 4 and 6, after meals 5-8
- fasting blood glucose and glucose tolerance testing
- HbA1c
- exercise and diet modification
- smoking cessation
what are antidiabetic agents
- oral
- injectable insulin
- drug used based on whether absolute insulin deficiency (type 1) or a defect in insulin action and secretion (type 2)
- type 1 diabetes: insulin is essential because there is no insulin being produced in the beta cells`
what are some dental considerations when a Pte is using insulin
- epi: caused hyperglycaemia – decreases the effectiveness of insulin, caution when using a local anesthetic containing EPI
- hypoglycaemia: monitor dental patient, make sure patient took insulin as prescribed and has eaten before the dental appt
what are some oral diabetic agents and what is their mechanism of action
- glyburide (diabeta)
- metformin
- glipizide
- rosiglitazone
- all act by either:
- stimulating release of insulin from islet cells
- increasing the sensitivity of insulin receptors on target cells
what are some oral manifestations of diabetes
- xerostomia
- burning tongue/mouth
- candida (fungal) infections
patients with diabetes should do what before tx
- eat!!!! also take their meds
what is thyroxine
- major hormone secreted by thyroid gland, requires iodine for synthesis
- used for therapeutic purposes because more constant blood levels
- max absorption on empty stomach
how do we test for thyroid disease
- blood test is taken that measures unbound T4 and TSH levels
what are s&s of hyperthyroidism
- sweating, weight loss, nervousness, oversensitive to heat, fatigue, moist skin, tachycardia (in graves disease, there is bulging of the eyes)
what are s&s of hypothyroidism
- cold intolerance, weakness, tiredness, fatigue, hoarseness, constipation, aches, pains
- myxedema (severe hypothyroidism)
what are drugs for hyperthyroidism
- thioamide drugs:
- propylthiouracil
- methimazole
- inhibit thyroid hormone production by interfering within the incorporation of iodine
- radioactive iodine, or iodine
what are thyroid replacement drugs
- for hypothyroidism
- thyroid USP
- levothyroxine
- L-triiodothyronine
what are adverse events regarding thyroid replacement drugs
- excessive doses of thyroxine can lead to heart disorders, including congestive heart failure and MI
- thyroid USP may cause allergic run since it is derived from animal sources
what is contraindicated in ptes with thyroid storm
- epi
what are 3 types of corticosteroid (think 3 Ss)
- mineralocorticoids (aldosterone - salt)
- glucocorticoids (cortisol - sugar)
- gonadocorticoids (sex hormones)
how does glucose affect metabolism (glucocorticosteroids)
- can affect glucose metabolism
- naturally occurring steroids cause proteins and lipids to be broken down and converted into glucose
- cause carbs stored in the form of glycogen to be converted back to glucose and deposited into the blood
what do glucocovrticosteroids do
- suppress the inflammatory process within the body, ie bee sting, arthritis
- no use naturally occurring steroids but have been replaced by others that can be produced more economically
- products: systemic, injectable, topical
what are indications for use of glucocorticosteroids
- Addisons disease
- systemic lupus erythematosus
- control inflammation (asthma, skin, IBS) –unclear mechanism of action; stabilize individual cells and their internal structures so that they do not release the substances (eg histamine) that initiate the irritation, pain and inflammation
- dental related ulcerative inflammatory lesions such as lichen plants, burning tongue, and aphthous stomatitis (canker sores)
- bulls disorders (eg pemphigus vulgaris and erythema multiforme)
- suppress the immune system: allergies, seasonal rhinitis
- leukemias, lymphomas
- ulcerative colitis, crohns disease
how do we classify glucocorticosteroids
- according the duration of action: short-acting, intermediate-acting, long-acting
- according the anti-inflammatory potency: hydrocortisone – least anti-inflammatory; betamethasone and dexamethasone – most potent anti-inflammatory
what are some side effect too glucocorticosteroids
- muscle weakness
- hyperglycemia
- intraoral candidiasis
- immune suppression
- ulcers
- poor wound healing
- diabetes (increase glucose secretion)
- less calcium absorption and increase calcium excretion via kidneys (removes calcium from bones – osteoporosis)
- shutdown of adrenal glands: life threatening, see after long-term use or after discontinuing the steroid, glands unable to immediately start normal levels of production, reversible with time, important to monitor dosage and response
how do we dose glucocorticosteroids
- alternate-day dosing should be use in long-term therapy
- doubling the dosage an administering the drug every other day in the morning mimics the endogenous (own body) corticosteroid circadian rhythm)
- goal is to maintain the lowest dose possible while obtaining a desired clinical response
what are some contraindications/precautions for using glucocorticosteroids
- herpes simplex
- glaucoma
- diabetes mellitus
- peptic ulcer disease
- osteoporosis
- congestive heart failure
- hypertension
- infections (fungal, bacterial, etc)
- psychiatric disorders
what is withdrawal from corticosteroids like
- ‘tapering’ period
- that that patients do not experience withdrawal syndrome – allows the body to recover the norma secretion of endogenous corticosteroids. in most ptes, the dosage is tapered over 2 months or more
- symptoms of rapid withdrawal: headache, fatigue, joint pain, nausea, vomiting, weight loss, fever, peeling of skin
when would drug interactions with corticosteroids require steroid levels be decreased
- carbamazepine
- phenobarbitals
- phenytoin
- rifampin
what are topical glucocorticosteroids classified by
- according to potency
- hydrocortisone is the least potent and best to use in infants and children because of minimal systemic absorption
when is an increase in dose of corticosteroids necessary
- for ptes undergoing stressful dental procedures like extractions, periodontal surgery and implant surgery
what are sex hormones and what are they produced by
- steroids produced from cholesterol
what are female sex hormones
- estrogens and progestins, including progesterone
- estradiol = main estrogen secreted by ovary
- estrone
- estriol
what is the major male sex hormone
- androgens, which includes testosterone
what are indications for the use of estrogens
- hormone replacement therapy to reduce the symptoms of menopause
- oral contraceptives in combination with progestins
- treatment of uterine bleeding due to hormone imbalance
- amenorrhea (lack of menstruation)
- certain carcinomas
- vulvar and vaginal atrophy
- prevention and tx of osteoporosis
- treatment of skin lesions (ie acne)
when is estrogen contraindicated
- in ptes with:
- breast cancer (uterus, cervix and vaginal cancer)
- pregnancy
- liver disease
- vascular thromboembolic (blood clot) condition – increased risk to blood clots if Pte smokes and takes the pill
- increased risk especially if used long term of cerebral vascular accident (stroke, particularly in smokers
what are some adverse effects of estrogen
- endometrial hyperplasia
- gallbladder disease
- increased incidence of breast cancer in ptes taking estrogen on a long term basis is controversial
- additionally, estrogen cause neasue and vomiting, headache, dizziness and breast tenderness
what are the main female sex hormones used in bc
- estrogen and progestins
what does bc do
- prevent ovulation
- stop secretion of FSH and LH
what are the 3 basic formulations of BC: estrogen and progestin
- monophonic: provides a constant amount of estrogen and progestin throughout the menstrual cycle
- biphasic: estrogen level stays the same, progestin level increases toward end of cycle
- triphasic: amount of estrogen and progestin vary in 3 phases during 28 day cycles
what is the progestin only bc and when is it used
- ‘minipill’
- less effective than estrogen and progestin oc
- for patients at high risk for side effects from estrogen
what are some drug interactions with bc
- antibiotics
- warfarin
- phenytoin
what does plan B do
- each tablet contains .75 mg of levonorgestrel
- 2 pills you take together
- temporarily stops the release of an egg from the ovary
- prevents fertilization
- prevents a fertilized egg from attaching to the uterus
- not an abortion pill – will not terminate pregnancy
- SE: vomiting, nausea, spotting
what is mifepristone
- called the ‘morning after’
pill, which is used to abort a fetus
what is testosterone used to treat
- hypogonadism (diminished function of the testes)
- most testosterone products undergo extensive first pass metabolism in the liver, reducing the oral bioavailability. thus, most products are given parentally (IM), buccally, or transdermally (through the skin)
what are anabolic steroids
- testosterone-like compounds with hormonal activity
- used inappropriately by athletes to increase muscle mass and strength
