pharmacology 3 Flashcards
HMG-CoA Reductase Inhibitors
the Statins!
pravastatin (Pravachol)
simvastatin (Zocor)
atorvastatin (Lipitor)
fluvastatin (Lescol)
rosuvastatin (Crestor)
pitavastatin (Livalo)
HMG-CoA Reductase Inhibitors
Mild, transient GI disturbances
Rash
Headache
Myopathy (muscle pain), possibly leading to the serious condition rhabdomyolysis
Elevations in liver enzymes or liver disease
rhabdomyolysis
breakdown of muscle, enzymes are released and it can lead to kidney damage and failure
HMG-CoA Reductase Inhibitors
oral anticoagulants
drugs metabolized by CYP3A4
(erythromycin
Azole antifungals
verapamil
diltiazem
HIV protease inhibitors
amiodarone)
Grapefruit juice
Bile Acid Sequestrants
sequester bile acid - Prevent resorption of bile acids from small intestine - Bile acids are necessary for absorption of cholesterol
cholestyramine (Questran)
colestipol (Colestid)
colesevelam (Welchol)
cannot be taken with other meds. either an hour before or 4-6 hours after
Bile Acid Sequestrants: Adverse Effects
Constipation
Heartburn, nausea, belching, bloating
These adverse effects tend to disappear over time
Bile Acid Sequestrants: Indications
Type II hyperlipoproteinemia
Relief of pruritus associated with partial biliary obstruction (cholestyramine)
May be used along with statins
Bile Acid Sequestrants Contraindications
PKU
Niacin (Nicotinic Acid)
Vitamin B3 - higher dose than normal vitamins
Effective, inexpensive, often used in combination with other lipid-lowering drugs
start with a low dose and gradually increase to prevent puritis and flushing
Niacin: Indications
Effective in lowering triglyceride, total serum cholesterol, and LDL levels
Increases HDL levels
Niacin: Adverse Effects
Flushing (caused by histamine release)
Pruritus
GI distress
Fibric Acid Derivatives Examples
Also known as fibrates
gemfibrozil (Lopid)
fenofibrate (Tricor)
Fibric Acid Derivatives: Indications
hyperlipidemia
Fibric Acid Derivatives: Adverse Effects
Abdominal discomfort, diarrhea, nausea
Blurred vision, headache
Increased risk of gallstones - unique to this set
Prolonged prothrombin time
Liver studies may show increased enzyme levels
Fibric Acid Derivatives: Interactions
oral anticoagulants
statins (risk for myositis, myalgias, and rhabdomyolysis is increased)
Decreased hemoglobin level, hematocrit value, and white blood cell count
Increased activated clotting time, lactate dehydrogenase level, and bilirubin level
Cholesterol Absorption Inhibitor
ezetimibe (Zetia)
ezetimibe (Zetia)
Inhibits absorption of cholesterol and related sterols from the small intestine
Results in reduced total cholesterol, LDL, and triglyceride levels
Also increases HDL levels
Often combined with a statin drug
Clinical trials continue >Currently recommended only when patients have not responded to other therapy
Herbal Product: Garlic
Used as an antispasmodic, antihypertensive, antiplatelet, lipid reducer
Possible interactions with warfarin, diazepam
May enhance bleeding when taken with NSAIDs
» stop taking prior to surgery
Garlic Adverse Effects
dermatitis, vomiting, diarrhea, flatulence, antiplatelet activity
Herbal Product: Flax
Both the seed and oil of the plant are used
Uses: atherosclerosis, hypercholesterolemia, GI distress, menopausal symptoms
May cause diarrhea and allergic reactions. Not recommended during pregnancy
Possible interactions: antidiabetic drugs, anticoagulant drugs
Herbal Product: Omega-3 Fatty Acids
Fish oil products
Used to reduce cholesterol
May cause rash, belching, allergic reactions
Potential interactions with anticoagulant drugs
Nursing Implications for Lipid Lowering Meds
health and medication history
Assess dietary patterns, exercise level, weight, height, vital signs, tobacco and alcohol use, family history
Assess for contraindications, conditions that require cautious use, and drug interactions
Obtain baseline liver function studies
Contraindications for Lipid Lowering Meds
Contraindications include biliary obstruction, liver dysfunction, active liver disease
Niacin contraindications
Gout
Lipid lowering meds: how long does it take for these drugs to take effect?
several weeks
Niacin and NSAIDs
Small doses of aspirin or NSAIDs may be taken 30 minutes before niacin to minimize cutaneous flushing
Lipid Lowering Agents: what to report
persistent GI upset, constipation, abnormal or unusual bleeding, and yellow discoloration of the skin
Low TSH
hyperthyroid
High TSH
hypothyroid
Hyperthyroid s/s
Tachycardia, heat intolerance, tremors, agitation, high BP
Hypothyroid
cold intolerant, low BP and heart rate
Cretinism
low thyroid in youth
Low metabolism, delayed growth and sexual development, possible retardation. Testing at birth to identify & treat!
Myxedema
low thyroid as an adult
Low metabolism, decrease mental, physical stamina, weight gain, hair loss, firm edema
Levothyroxine
(synthroid, levoxyl, synthetic T4)
25-200mcg./day; chemically pure; more predictable results; adults and children
take in the morning to avoid sleep disturbances
Dessicated thyroid shit
Animal source; “natural”; consists of pulverized cow or pig thyroid. Results variable
60-65 mg. (1 gr.) Armour Thyroid
Thyroid Replacement: Adverse Reaction
Usually the result of overdose; is essentially an induced state of hyperthyroidism!
Cardiac: dysrhythmia, tachycardia, hypertension, Recent MI is contraindication
CNS: insomnia, tremor, headache, anxiety
GI: nausea, diarrhea, appetite change
Other: menstrual irregularity, wt. loss, heat intolerance
Thyroid Replacement: Interactions
anticoagulants
With digitalis, may decrease levels
Cholestyramine binds in gut reducing absorption of both
May increase need for insulin in diabetes
Cardiac patient using epinephrine may induce coronary insufficiency
Inappropriate/overuse associated with osteoporosis
when to take levothyroxine
Best taken in AM: 30-60 minutes before food
Hashimoto’s Thyroiditis
Test for anti-thyroid antibodies
Important cause of hypothyroidism
Autoimmune process; destruction of thyroid
Initially presents with symptoms of hyperthyroidism; may include Hashimoto’s psychosis!
Radioactive Iodine
Destroys the thyroid gland through ablation
Emits beta rays which destroy the tissue when taken up
Antithyroid drugs
tapazole (methimazole), PTU (propylthiouracil)
Inhibits iodine uptake preventing the formation of active T3, T4; dietary restrictions of iodine!
pregnancy and antithyroid
PTU first trimester, MMI, remainder of pregnancy
Tapazole(methimazole):
QD dosing; typically result in suppression in 6 weeks
can rarely cause agranulocytosis
PTU (propylthiouracil):
preferred for use in 1st trimester if indicated; takes 8 weeks or longer for suppression; BID-TID dosing
rarely cause agranulocytosis
Radioactive Iodine Testing/Ablation
Frequently used post thyroidectomy if further suppression indicated
Usually out-patient unless high doses anticipated (↑30 mci)
Stop synthroid 6 weeks before scan; begin cytomel
Stop cytomel 2 weeks before scan; need thyroid suppression
Low iodine diet 1 week before scan; low salt diet, no fish, shellfish, limit dairy to 8oz/day
2 days before scan check TSH to assure hypothyroid, pregnancy test
Radioactive Iodine Testing: Patient Teaching
Radioactive iodine is largely taken up by the thyroid. Residual amounts excreted over 2-3 days in urine, feces, saliva, sweat
Hand washing, personal towel, separate linens
Double flush toilet
No one closer than 3 feet for more than 1 hr/day
No pregnant women, minimize infant exposure
Side effect og magnesium containing antacid
diarrhea (milk of mag makes people poop)
Aluminum containing drugs can cause
constipation
Antidiarrheals carry a risk for
dependence (lomotoal)
Medications for Aids patients to stimulate appetites
Marinol
Helicobacter pylori (H. pylori)
PPI & Antibiotics are used together to eradicate H. pylori
* First-line therapy includes a 10- to 14-day course of a proton pump inhibitor (PPI) and the antibiotics clarithromycin and either amoxicillin or metronidazole or a combination of a PPI, bismuth subsalicylate, and the antibiotics tetracycline and metronidazole.
Testing for H. Pylori
blood: looks for antibodies and can test positive for years after initial infection even if the patient is over it. best for young people
stool: best for older people or those previously treated. no ppi for 2 weeks before test, no bismuth for 1 month before test
breath: not always available, great at any point in treatment and you just need to be NPO for 6 hours before test
Histamine blockers: Adverse Effects
confusion
CV: hypotension with IV use
CNS: headache, confusion, agitation
Endocrine: ↑ prolactin, gynecomastia (tagamet)
GI: diarrhea, nausea
Hepatobiliary: ↑ LFT, jaundice
Hematologic: numerous
Skin: urticaria, rash
