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Pharmacology of the Selected Endocrine Drugs
2005
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Endocrine Medications
Hormonal replacement
Endocrine Medications
Anti-diuretic hormones
• Enhance re-absorption of water in the kidneys
• Increases water permeability in the renal collecting ducts
• Also stimulates VASOCONSTRICTION and increases the blood pressure
Endocrine Medications
Therapeutic Indications
1. Hormonal replacement
2. Used in diagnostic procedure
3. Used to control the hemorrhage in variceal bleeding
4. Treatment of enuresis
Endocrine Medications
Used in DI
• 1. Desmopressin and Lypressin intranasally
• 2. Pitressin IntraMuscularly
Endocrine Medications
Anti-diuretic hormones
SIDE-effects• Flushing and headache• Water intoxication• CVS: heart block, MI• Renal: hyponatremia• Gangrene due to vasoconstriction
Thyroid Medications
Thyroid hormones
• These products are used to treat the manifestations of hypothyroidism
• Replace hormonal deficit in the treatment of HYPOTHYROIDSM
Thyroid Medications
Thyroid hormones
• Levothyroxine (Synthroid)
• Liothyroxine (Cytomel)
• Thyroid dessicated
• Liotrix (Thyrolar)
Thyroid Medications
Thyroid hormones: Actions
• Replaces both T3 and T4
• Increases metabolic rate
Thyroid Medications
Thyroid hormones: Actions
• Increase the metabolic rate
• Increase O2 consumption
• Increase HR, RR, BP
Thyroid Medications
Thyroid hormones: Indications
Hypothyroidism
Diagnostic suppression test
Thyroid Medications
Thyroid hormones
Side-effects
1. Nausea and Vomiting
2. Signs of increased metabolism= tachycardia, hypertension, cardiac arrhythmias, anxiety, headache, tremors, palpitations
Thyroid Medications
Thyroid hormones : Nursing responsibility
1. Monitor weight, VS
2. Instruct client to take daily medication the same time each morning WITHOUT FOOD
Monitor blood tests to check the activity of thyroid
Thyroid Medications
Thyroid hormones: Nursing responsibility
3. Advise to report palpitation, tachycardia, and chest pain
4. Instruct to avoid foods that inhibit thyroid secretions like cabbage, spinach and radishes
ANTI-Thyroid Medications
ANTI-THYROID medications
• The thyroid becomes oversaturated with iodine and stop producing thyroid hormone
ANTI-Thyroid Medications
ANTI-THYROID medications
• Drugs used to BLOCK the thyroid hormones and treat hyperthyroidism
• Inhibit the synthesis of thyroid hormones
ANTI-Thyroid Medications
ANTI-THYROID medications
1. Methimazole (Tapazole)
2. PTU (prophylthiouracil)
3. Iodine solution- SSKI and Lugol’s solution
ANTI-Thyroid Medications
ANTI-THYROID medications: Indications
1. Grave’s dosease
2. Thyrotoxicosis
ANTI-Thyroid Medications
ANTI-THYROID medications:
• Absorption is good orally
ANTI-Thyroid Medications
ANTI-THYROID medicationsSide-effects of thionamides
–N/V, drowsiness, lethargy, bradycardia, skin rash
–GI complaints–Arthralgia, myalgia–AGRANULOCYTOSIS
• Most important to monitor
ANTI-Thyroid MedicationsANTI-THYROID medicationsSide-effects of Iodine solutions
Lugol’s–Most common adverse effects is
HYPOTHYROIDISM– Iodism= metallic taste, burning in
the mouth, sore teeth and gums, diarrhea, stomach upset
ANTI-Thyroid Medications
ANTI-THYROID medicationsNursing responsibilities• 1. Monitor VS, T3 and T4,
weight• 2. The medications WITH
MEALS to avoid gastric upset
ANTI-Thyroid Medications
ANTI-THYROID medications Nursing responsibilities
• 3. Instruct to report SORE THROAT or unexplained FEVER
• 4. Monitor for signs of hypothyroidism. –Instruct not to stop abrupt
medication
ANTI-Thyroid MedicationsANTI-THYROID medicationsLugol’s Solution• Used to decrease the vascularity and size of
the thyroid (in preparation for thyroid surgery)
• T3 and T4 production diminishes• Given per orem, can be diluted with juice,
administered WITH foods• Use straw to decrease staining• Monitor iodism
STEROIDS
• Replaces the steroids in the body
• Cortisol, cortisone, betamethasone, and hydrocortisone
STEROIDS
• These drugs enter the cells and bind to receptors
• They inhibit the enzyme phospholipase
STEROIDS• Corticosteroids are used topically
and locally to achieve the desired anti-inflammatory effects at a particular site
Examples:PrednisoneBethamethasonePrednisoloneFludrocortisone
STEROIDSSide-effects
–HYPERglycemia–Increased susceptibility to
infection (immunosuppression)
–Hypokalemia–Edema–Peptic ulceration
STEROIDS
Side-effects–If high doses- osteoporosis, growth retardation, peptic ulcer, hypertension, cataract, mood changes, hirsutism, and fragile skin
STEROIDS
• Nursing responsibilities
1. Monitor VS, electrolytes, glucose
2. Monitor weight edema and I/O
STEROIDS• Nursing responsibilities
3. Protect patient from infection
4. Handle patient gently
5. Instruct to take meds WITH MEALS to prevent gastric ulcer formation
STEROIDS• Nursing responsibilities
6. Caution the patient NOT to abruptly stop the drug
7. Drug is tapered to allow the adrenal gland to secrete endogenous hormones
STEROIDS
Evaluation:
The drugs are effective if there is:
1. Relief of signs and symptoms of inflammation
2. Return of adrenal function to normal
DM Drug therapy
DRUG THERAPY and MANAGEMENT
• Usually, this type of management is employed if diet modification and exercise cannot control the blood glucose level.
DRUG THERAPY and MANAGEMENT
• These agents are employed to control the blood glucose level
• They can be insulin and oral agents
• These are given to replace the hormone in the body
• If hormone is still present BUT decreased, Oral agents are given
Diabetes Mellitus
DRUG THERAPY and MANAGEMENT
• Because the patient with TYPE 1 DM cannot produce insulin, exogenous insulin must be administered for life.
Diabetes Mellitus
DRUG THERAPY and MANAGEMENT
• TYPE 2 DM may have decreased insulin production, ORAL agents that stimulate insulin production are usually employed.
Diabetes Mellitus
PHARMACOLOGIC INSULIN• This may be grouped into several
categories according to:1. Source- Human, pig, or cow2. Onset of action- Rapid-acting, short-acting, intermediate-acting, long-acting and very long acting
Diabetes Mellitus
PHARMACOLOGIC INSULIN
• This may be grouped into several categories according to:
3. Pure or mixed concentration
4. Manufacturer of drug
Diabetes Mellitus
GENERALITIES
• 1. Human insulin preparations have a shorter duration of action than animal source
Diabetes Mellitus
GENERALITIES
• 2. Animal sources of insulin have animal proteins that may trigger allergic reaction and they may stimulate antibody production that may bind the insulin, slowing the action
Diabetes Mellitus
• 3. ONLY Regular insulin can be used INTRAVENOUSLY!
Diabetes Mellitus
• 4. Insulin are measured in INTERNATIONAL UNITS or “iu”
• 5. There is a specified insulin injection calibrated in units
Diabetes Mellitus
• Mixed insulin are also available
• The msot common of which is the 70-30 insulin
• Made up of :70% NPH and 30% regular insulin in the vial
Comparison of Insulin Peak action
Insulin Type Example Onset PEAK
ULTRA-acting Lispro 15 minutes
1 hour
RAPID acting Regular Insulin
1 hour 2-4 hrs
Intermediate acting
NPH and Lente
1 ½ to 2 hrs
6-8 hrs
to 12 hrs
Long Acting Ultra-lente 4-8 hrs 10-20 hrs
Diabetes Mellitus
RAPID ACTING INSULIN
• Lispro (Humalog) and Insulin Aspart (Novolog)
• Produces a more rapid effect and with a shorter duration than any other insulin preparation
Diabetes Mellitus
RAPID ACTING INSULIN
• ONSET- 5-15 minutes
• PEAK- 1 hour
• DURATION- 3 hours
• Instruct patient to eat within 5 to 15 minutes after injection
Diabetes Mellitus
REGULAR INSULIN
• Also called Short-acting insulin
• “R”
• Usually Clear solution administered 30 minutes before a meal
Diabetes Mellitus
REGULAR INSULIN• ONSET- 30 minutes to 1
hour• PEAK- 2 to 4 hours• DURATION- 4 to 6 hours
Diabetes Mellitus
INTERMEDIATE ACTING INSULIN
• Called “NPH” or “LENTE”
• Appears white and cloudy
Diabetes Mellitus
INTERMEDIATE ACTING INSULIN
• ONSET- 2-4 hours• PEAK- 4 to 6-12 hours• DURATION- 16-20 hours
Diabetes Mellitus
LONG- ACTING INSULIN• “UltraLENTE”• Referred to as “peakless”
insulin
Diabetes Mellitus
LONG- ACTING INSULIN
• ONSET- 6-8 hours
• PEAK- 12-16 hours
• DURATION- 20-30 hours
Diabetes Mellitus
HEALTH TEACHING
Regarding Insulin SELF- Administration
• 1. Insulin is administered at home subcutaneously
Diabetes Mellitus
HEALTH TEACHING Regarding Insulin SELF- Administration
• 2. Cloudy insulin should be thoroughly mixed by gently inverting the vial or ROLLING between the hands
Diabetes Mellitus
HEALTH TEACHING Regarding Insulin SELF- Administration
• 3. Insulin NOT IN USE should be stored in the refrigerator, BUT avoid freezing/extreme temperature
Diabetes Mellitus
• 4. Insulin IN USE should be kept at room temperature to reduce local irritation at the injection site
Diabetes Mellitus
• 5. INSULIN may be kept at room temperature up to 1 month
Diabetes Mellitus
• 6. Select syringes that match the insulin concentration.–U-100 means 100 units per mL
Diabetes Mellitus
• 7. Instruct the client to draw up the REGULAR (clear) Insulin FIRST before drawing the intermediate acting (cloudy) insulin
Diabetes Mellitus
• 8. Pre-filled syringes can be prepared and should be kept in the refrigerator with the needle in the UPRIGHT position to avoid clogging the needle
Diabetes Mellitus
• 9. The four main areas for insulin injection are- ABDOMEN, UPPER ARMS, THIGHS and HIPS
Diabetes Mellitus
• Insulin is absorbed fastest in the abdomen and slowest in the hips
• Instruct the client to rotate the areas of injection, but exhaust all available sites in one area first before moving into another area.
Diabetes Mellitus
• 10. Alcohol may not be used to cleanse the skin
• 11. Utilize the subcutaneous injection technique- commonly, a 45-90 degree angle.
Diabetes Mellitus
• 12. No need to instruct for aspirating the needle
• 13. Properly discard the syringe after use.
Diabetes Mellitus
T-I-E
Test blood Inject insulin Eat food
Diabetes Mellitus
ORAL HYPOGLYCEMIC AGENTS
• These may be effective when used in TYPE 2 DM that cannot be treated with diet and exercise
• These are NEVER used in pregnancy!
Diabetes Mellitus
ORAL HYPOGLYCEMIC AGENTS• There are several agents:
–Sulfonylureas–Biguanides–Alpha-glucosidase inhibitors–Thiazolidinediones–Meglitinides
Diabetes Mellitus
ORAL HYPOGLYCEMIC AGENTS• These drugs are given per orem and
are effective only in type 2 DM
• Common adverse effects include:– Hypoglycemia– Diarrhea, jaundice, nausea and
heartburn– Anemia , photosensitivity
Diabetes Mellitus
ORAL HYPOGLYCEMIC AGENTSGeneral Nursing Consideration1. Observe for manifestations of
hypoglycemia2. Assess for allergic reaction3. Instruct to take the medication at the
same time each day4. Caution to avoid taking other drugs
without consultation with physician
Diabetes Mellitus
ORAL HYPOGLYCEMIC AGENTSGeneral Nursing Consideration5. THESE medications SHOULD NEVER
be given to pregnant women, so rule out pregnancy
6. Instruct to wear sunscreen7. Advise to bring simple sugar to be
taken when hypoglycemic episodes occur
Diabetes Mellitus
SULFONYLUREAS• MOA- stimulates the beta
cells of the pancreas to secrete insulin
• Classified as to generations- first and second generations
Diabetes Mellitus
SULFONYLUREAS
• FIRST GENERATION- Acetoheximide, Chlorpropamide, Tolazamide and Tolbutamide
• SECOND GENERATION- Glipizide, Glyburide, Glibenclamide, Glimepiride
Diabetes Mellitus: Sulfonylureas
• The most common side –effects of these medications are Gastro-intestinal upset and dermatologic reactions.
• HYPOGLYCEMIA is also a very important side-effect
• Given 30 minutes before meals- breakfast
Diabetes Mellitus: Sulfonylureas
• Chlorpropamide has a very long duration of action. This also produces a disulfiram-like reaction when taken with alcohol
• Second generation drugs have shorter duration with metabolism in the kidney and liver and are the choice for elderly patients
Diabetes Mellitus
BIGUANIDES• MOA- Facilitate the action of
insulin on the peripheral receptors
• These can only be used in the presence of insulin
Diabetes Mellitus
BIGUANIDES= “formin”• They have no effect on the
beta cells of the pancreas • Metformin (Glucophage) and
Phenformin are examples
Diabetes Mellitus: Biguanides
• The most important side effect is LACTIC ACIDOSIS!
• These are not given to patient with renal impairment
Diabetes Mellitus: Biguanides
• These drugs are usually given with a sulfonylurea to enhance the glucose-lowering effect more than the use of each drug individually
Diabetes Mellitus
ALPHA-GLUCOSIDASE INHIBITORS• MOA- Delay the absorption of glucose in
the GIT • Result is a lower post-prandial blood
glucose level• They do not affect insulin secretion or
action!• Side-effect: DIARRHEA and
FLATULENCE
Diabetes Mellitus
• Examples of AGI are Acarbose and Miglitol
• They are not absorbed systemically and are very safe
• They can be used alone or in combination with other OHA
Diabetes Mellitus
• Side-effect if used with other drug is HYPOGLYCEMIA
• Note that sucrose absorption is impaired and IV glucose is the therapy for the hypoglycemia
Diabetes Mellitus
THIAZOLIDINEDIONES• MOA- Enhance insulin
action at the receptor site• They do not stimulate
insulin secretion
Diabetes MellitusTHIAZOLIDINEDIONES
• Examples- Rosiglitazone, Pioglitazone• These drugs affect LIVER FUNCTION• Can cause resumption of OVULATION
in peri-menopausal anovulatory women
Diabetes Mellitus
MEGLITINIDES• MOA- Stimulate the
secretion of insulin by the beta cells
• Examples- Repaglinide and Nateglinide
Diabetes Mellitus
MEGLITINIDES
• They have a shorter duration and fast action
• Should be taken BEFORE meals to stimulate the release of insulin from the pancreas
Diabetes Mellitus
MEGLITINIDES• Principal side-effect of
meglitinides- hypoglycemia• Can be used alone or in
combination
Reproductive Hormones
• Gonadal hormones include agents that affect the female and male reproductive cycle
• Female hormones include ESTROGENS, PROGESTINS and ovarian hormones
• Male hormones include ANDROGENS and anabolic steroids
Reproductive Hormones
The GENERAL Mechanism of Action
• These hormones interfere with the normal cycle of hormone balance
Reproductive Hormones
INDICATIONS
1. FEMALE: Hormonal replacement therapy, oral contraception, treatment of infertility and management of some tumors
2. MALE: replacement therapy, metabolic stimulators and treatment of some tumors
Reproductive Hormones
Estrogens
• Conjugated estrogen
• Estradiol
• Ethinyl estradiol
• Diethylstilbesterol (DES)
• Clomiphene
Reproductive Hormones
Progestins• Medroxyprogesterone acetate
(Provera)• Megestrol• Norethindrone• Levonorgestrel (Norplant)• Norgestrel• Norethindrone acetate
Reproductive Hormones
Androgens
• Testosterone cypionate
• Methyltestosterone
• Fluoxymesterone
• Aqueous testosterone
Reproductive Hormones
Oral Contraceptive Pills
• Two types are available: Combination estrogen and progesterone AND progestins only
Reproductive Hormones
Oral Contraceptive Pills: DYNAMICS
• Inhibits OVULATION by altering the hypothalamus and gonadotropin axis
• Alters the MUCUS to prevent sperm entry
• Alters the uterine endometrium to prevent implantation
• Suppresses the ovaries
Reproductive Hormones
Oral Contraceptive Pills: Indicators
• Suppression of ovulation for prevention of pregnancy
• Regulation of menstrual cycle and management of dysfunctional bleeding
• Treatment of endometriosis
Reproductive Hormones
Oral Contraceptive Pills: Kinetics
• Easily absorbed orally
• NORPLANT provides 5 years of contraception
• Provera provides 3 months of protection
• Metabolized and excreted in liver
Reproductive Hormones
Oral Contraceptive Pills:
• Not to be used in patients with history of, hypertension, thromboemoblic or CVA disease
• Not given in certain cancers
• Contraindicates in pregnancy
• SMOKING should be avoided when under therapy
Reproductive Hormones
Oral Contraceptive Pills: Drug Interaction
• Rifampicin, penicillin and tetracycline REDUCE effectiveness of contraception
• Benzodiazepines decrease the levels of OCP
Reproductive Hormones
Oral Contraceptive Pills:
Side effects
• CNS: headache
• CV: Thromboembolic disease, MI, hypertension and pulmonary edema
• NAUSEA and cholestatic JAUNDICE
• Breast tenderness, weight gain, edema, breakthrough bleeding, acne
Reproductive hormones
Nursing Considerations1. Assess for risk factors and the ability to
comply with medications2. Determine the type of OCP used• Monophasic pills provide constant dosing
of BOTH estrogen and progestin• Biphasic pills provide constant estrogen
but varying progestin doses• Triphasic pills provide varying Estrogen
and Progesterone
Reproductive hormones
Nursing Considerations3. Teach the common side-effects and re-
assure that these will decrease in time4. Instruct to use other means of
contraception if antibiotics and anticonvulsants are also taken
5. WARNT the client to avoid smoking because this will increase the risk for embolic episodes
Clomiphene
• A synthetic, non-steroidal estrogen
• Increases the secretion of gonadotropins and initiates the secretion of FSH and LH
• OVULATION will occur
• Used in the treatment of infertility
• Readily absorbed orally
Clomiphene
• Side effects can be:
• Risk for Multiple pregnancy
• Nausea, breast discomfort, headache and GI disturbances
• Visual disturbances
• Enlargement of the ovaries
Viagra (Sildenafil)
• A medication used for penile erectile dysfunction
• Selectively inhibits receptors and enzyme Phosphodiesterase E
• This increases the nitrous oxide levels allowing blood flow into the corpus cavernosum
Viagra (Sildenafil)
• Contraindicated in patients with bleeding disorders and with penile implants
• Caution: Coronary Artery Disease and concomitant use of nitrates
• Side-effects: PRIAPISM, headache, flushing, dyspepsia, UTI, diarrhea and dizziness
Viagra (Sildenafil)
• Nursing consideration
• Assess for risk factors
• Instruct to take the drug ONE hour before sexual act
• Drug is taken orally
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