NUR 3420 Pharmacology PrepU Chapter 42

A client is receiving a thyroid hormone to treat hypothyroidism. Which would indicate to the nurse that the client needs a reduced dosage of the drug?

Tachycardia Explanation: Tachycardia suggests hyperthyroidism due to excessive thyroid hormone; this would require a reduction in dosage. The other responses suggest hypothyroidism and drug ineffectiveness.

A female client with a six-month-old infant has been prescribed propylthiouracil (PTU). What is the most important question the nurse should ask this client?

"Are you breastfeeding your child?" Explanation: Mothers taking PTU should not breastfeed their children (pregnancy category D). For the safety of the infant, the nurse should ask the client if she's breastfeeding. Taking thyroid medications in the past does not have an immediate impact on safety for the client or infant. Using PTU during pregnancy can cause hypothyroidism in the fetus. The time frame in which the client has had thyroid-related symptoms does not have an immediate effect on safety of the client or infant.

A nurse is providing education to a client who will soon begin taking levothyroxine for the first time. Which teaching point should the nurse include in this education session?

"You'll most likely take this drug for the rest of your life." Explanation: Levothyroxine is normally taken for the duration of the client's life. It is only administered by the IV route in cases of myxedema coma. It does not require a strict diet of high protein and low carbohydrates and it does not create a need for blood glucose monitoring. The medication should be taken on an empty stomach at least one hour before breakfast or two hours after a meal.

Knowing that thyroid hormones are principally concerned with the increase in metabolic rate of tissues, which symptom would a nurse observe in a client with uncontrolled hyperthyroidism? (Select all that apply.)

- Weight loss - Tachycardia Explanation: The signs and symptoms of hyperthyroidism include increased metabolism, heat intolerance, elevated body temperature, weight loss, tachycardia, hypertension, nervousness, anxiety, insomnia, exophthalmos, flushed (warm, moist, red) skin, thinning hair, goiter, and irregular or scant menses.

When providing care for a client who has been admitted with clinical hypothyroidism, the nurse should implement what intervention to address common characteristics of the disorder? Select all that apply.

- monitor for constipation - implement falls risk precautions - maintain a warm room temperature Explanation: Clinical hypothyroidism produces variable signs and symptoms, depending on the amount of circulating thyroid hormone. Initially, manifestations are mild and vague. They usually increase in incidence and severity over time as the thyroid gland gradually atrophies. Clients with hypothyroidism are frequently cold intolerant; a warm environmental temperature is warranted. Signs and symptoms of hypothyroidism can also include weakness, tiredness, slow speech and body movements, emotional and mental dullness, excessive sleeping, constipation, and skin changes. There is no need for either constant oxygen monitoring or a low-calorie diet.

A primary health care provider has prescribed levothyroxine to a client with hypothyroidism. Which information would the nurse include in the teaching plan to promote an optimal response to the drug therapy?

Administer the drug early in the morning before breakfast. Explanation: The nurse should instruct the client to administer the drug early in the morning before breakfast to promote an optimal response to the drug therapy since an empty stomach increases the absorption of the oral preparation. When methimazole and propylthiouracil are administered to the client, the nurse should recommend that the client record the pulse rates and bring the record to the primary health care provider. If the client expresses a concern about the dosage schedule, the nurse can offer suggestions to the client about the dosage schedule. If the client experiences a rash while taking methimazole or propylthiouracil, the nurse needs to inform the client to apply soothing creams or lubricants.

A nurse is caring for a patient suffering from a severe form of hyperthyroidism called thyrotoxicosis or thyroid storm. Which of the following should the nurse observe in the patient as a characteristic of thyroid storm?

Altered mental status Explanation: A severe form of hyperthyroidism called thyrotoxicosis or thyroid storm is characterized by high fever, extreme tachycardia, and altered mental status. The nurse need not observe memory impairment, cold intolerance, or constipation as characteristics of thyroid storm. Memory impairment, cold intolerance, and constipation are the manifestations of myxedema, which is a severe hypothyroidism.

The treatment protocol for a client with hyperthyroidism includes antithyroid medication and propranolol. The purpose of propranolol is to do which of the following?

Decrease tachycardia Explanation: Propranolol is an adrenergic blocking agent. It is prescribed as adjunctive treatment for several weeks during antithyroid treatment, until the therapeutic effects of the antithyroid drug are obtained. Propranolol decreases tachycardia and palpitations, but it does not decrease the risk of infection or relieve coughing. People with hyperthyroidism tend to have difficulty with keeping weight on, a medication to enhance this effect would not be prescribed as part of the client's treatment.

The most common cause of subclinical hyperthyroidism is:

Excess thyroid hormone therapy. Explanation: Clients should be monitored closely for hypothyroidism while taking antithyroid drugs, which usually develops within a year after receiving treatment for hyperthyroidism. The most common cause of subclinical hyperthyroidism is excess thyroid hormone therapy.

A nurse is caring for a client with subacute lymphocytic thyroiditis. The health care provider prescribes thyroid hormones to the client. From which sign during ongoing assessment should the nurse conclude that the client is responding to the therapy?

Extreme tachycardia Explanation: Signs of thyrotoxicosis (increased hyperthyroidism) include high fever, extreme tachycardia, and altered mental status. A sore throat would alert the nurse to possible agranulocytosis. Fatigue is a sign of hypothyroidism. Bruising is a sign of increased bleeding tendency, not hyperthyroidism.

Which would a nurse expect to assess in a client experiencing hyperthyroidism?

Flushed, warm skin Explanation: Clients with hyperthyroidism typically exhibit flushed, warm skin; hyperactive deep tendon reflexes; tachycardia; and intolerance to heat.

The nurse is preparing to administer levothyroxine to a client. Which assessment finding would cause the nurse to hold the medication?

Heart rate of 110 beats per minute Explanation: Levothyroxine should be held if the client's heart rate is over 100 beats per minute.

A client presents at the clinic reporting weight loss despite an increased appetite. For which condition should this client be assessed?

Hyperthyroidism Explanation: Hyperthyroidism is manifested by increased appetite and metabolism. Without treatment, it may be difficult for hyperthyroid individuals to consume enough calories to prevent weight loss. Hypothyroidism, which may be caused by thyroiditis, causes decreased appetite and metabolism, and hypothyroid patients frequently experience weight gain.

All of the following are specific physiological effects of thyroid hormones, EXCEPT:

Increased pituitary secretion of TSH. Explanation: Some specific physiologic effects of thyroid hormones include increased rate of cellular metabolism and oxygen consumption, with a resultant increase in heat production; increased heart rate, force of contraction, and cardiac output; increased carbohydrate metabolism; increased fat metabolism, including increased lipolytic effects of other hormones and metabolism of cholesterol to bile acids; and inhibition of pituitary secretion of TSH.

he pharmacology instructor is providing education regarding propylthiouracil to the nursing students. What would the instructor identify as the primary mode of action for this medication?

Inhibition of production of thyroid hormone Explanation: Propylthiouracil acts by inhibiting production of thyroid hormones and peripheral conversion of thyroxine (T4) to the more active triiodothyronine (T3).

When describing thyroid function, the nurse would emphasize the need for intake of:

Iodine Explanation: Iodine intake is necessary for the production of thyroid hormones.

A client is diagnosed with liver disease. How would this affect the metabolism of the drugs used to treat the client's hypothyroidism?

It would be prolonged. Explanation: Drug metabolism in the liver is delayed in clients with hypothyroidism and liver disease, so most drugs given to these clients have a prolonged effect.

An older adult has been prescribed a thyroid hormone replacement medication. The nurse should first clarify which prescription?

Levothyroxine (Synthroid) 150 mcg orally once per day Explanation: Synthroid is prescribed 100-125 mcg/day orally. A dose of 150 mcg orally once per day is outside of the normally prescribed range. The other medication doses are within recommended parameters. In addition, older adults are at higher risk of adverse reactions; therefore, a smaller dose is started initially and increased in small increments over a period of weeks.

The nurse cares for a client who was admitted for multiple bone fractures resulting from a fall. The client has a comorbidity of hypothyroidism. Which diet is the most appropriate for this client?

Low calorie, high fiber Explanation: Hypothyroidism slows the metabolism and decreases gastrointestinal secretions and motility. Hypothyroid clinets, therefore, should be encouraged to eat a low-calorie, high-fiber diets to combat weight gain and constipation.

A client is brought to the emergency department after taking an overdose of levothyroxine. When assessing this client, what adverse effects would the nurse expect to find?

Nervousness and tachycardia Explanation: Excessive doses of levothyroxine, a thyroid drug, can cause the same signs and symptoms that occur with hyperthyroidism. These include nervousness and tachycardia.

A client who has taken an overdose of levothyroxine (Synthroid) is brought to the Emergency Department. In assessing this client, what side effect would the nurse expect to find?

Nervousness, tachycardia, tremors Explanation: Excess thyroid hormone will produce symptoms similar to hyperthyroidism, which are nervousness, tachycardia, and tremors. It does not produce somnolence, bradycardia, paresthesia, hyperglycemia, hypertension, edema, buffalo hump, constipation, or sodium loss.

A client admitted to the hospital with hyperthyroidism treated with propylthiouracil suddenly develops a skin rash. Which action would the nurse implement first?

Notify the primary health care provider. Explanation: Whenever a client develops a skin rash after taking propylthiouracil, the nurse must notify the primary health care provider immediately because it may be an adverse reaction. The other measures are important to protect the skin integrity: avoid soap and apply soothing cream to affected areas. Recording the weight and reporting weight gain or loss are also important.

Which of the following drug types is most likely to cause respiratory depression and myxedema coma in clients with thyroid disorders?

Opioid analgesics Explanation: Clients with hypothyroidism are especially likely to experience respiratory depression and myxedema coma with opioid analgesics and other sedating drugs. These drugs should be avoided when possible.

Thioamide antithyroid drugs treat hyperthyroidism by inhibiting the synthesis of thyroid hormone. What is the prototype of the thioamide anti-thyroid drugs?

Propylthiouracil Explanation: Propylthiouracil is the prototype of the thioamide antithyroid drugs. Although propranolol is used to treat some symptoms of hyperthyroidism, it is an antiadrenergic, not an antithyroid drug. Sodium iodide is a radioactive isotope that decreases thyroid hormone production by destroying thyroid tissue. Levothyroxine is a thyroid drug.

The nurse is caring for a client who has a possible thyroid disorder and is aware that what medication will be used in diagnostic testing?

Sodium iodide131I Explanation: Sodium iodide131 I is used in the diagnosis of thyroid disease and also in the treatment of hyperthyroidism.

A nurse is caring for a patient undergoing thyroid hormone replacement therapy. What should the nurse inform this patient regarding administration of the drug?

Take the drug before breakfast. Explanation: The nurse should inform the patient undergoing thyroid hormone replacement therapy to take the drug in the morning, preferably before breakfast. The nurse should not ask the patient to take the drug before bedtime, just before dinner, or after lunch as that is not generally recommended by the health care provider.

During a general health assessment, a client indicates taking thyroid medication to increase weight loss. What statement should be the basis of the nurse's response?

Taking excessive or unnecessary thyroid medication may produce serious or life-threatening manifestations of toxicity. Explanation: The FDA has issued a black box warning regarding the use of thyroid hormones for the treatment of obesity or weight loss, either alone or with other therapeutic agents. Significant and serious complications may develop in euthyroid clients talking thyroid hormones.

A client admitted to the unit with adrenal insufficiency is subsequently diagnosed as also having hypothyroidism. Which statement describes appropriate treatment for this client?

The adrenal insufficiency should be treated before thyroid replacement is started. Explanation: When hypothyroidism and adrenal insufficiency coexist, the adrenal insufficiency should be treated before starting thyroid replacement. Thyroid hormones increase tissue metabolism and tissue demands for adrenocortical hormones. If adrenal insufficiency is not treated first, administration of thyroid hormone may cause acute adrenocortical insufficiency, a life-threatening condition.

The pharmacology instructor is providing education regarding propylthiouracil to the nursing students. What would the instructor identify as the primary mode of action for this medication?

The resident's apical heart rate is 112 beats/minute with a regular rhythm. Explanation: If the pulse rate is greater than 100 bpm, it is necessary to withhold a levothyroxine dose in an older adult. Anorexia, recent vaccination, and recent falls do not necessary indicate a need to withhold this medication.

The pharmacology instructor is talking about the drug propylthiouracil (PTU). What would the instructor cite as the primary mode of action for propylthiouracil (PTU)?

To inhibit production of thyroid hormone Explanation: PTU acts by inhibiting production of thyroid hormones and peripheral conversion of T4 to the more active T3.

Graves' disease is the most common cause of hyperthyroidism. True or False

True Explanation: Graves' disease, a poorly understood condition that is thought to be an autoimmune problem, is the most common cause of hyperthyroidism.

What is the most common cause of subclinical hyperthyroidism?

excess thyroid hormone therapy Explanation: The most common cause of subclinical hyperthyroidism is excess thyroid hormone therapy. Clients should be monitored closely for hypothyroidism while taking antithyroid drugs, which usually develops within a year after receiving treatment for hyperthyroidism. Common causes of primary hypothyroidism include treatment of hyperthyroidism with radiation therapy or surgery. Predisposing factors for myxedema coma include administration of central nervous system depressants. Untreated osteoporosis is not relevant to subclinical hyperthyroidism.

While the nurse is talking with a client, the client informs the nurse that the client has been under treatment for weight loss management. The client indicates taking antithyroid medication to increase weight loss. Included in client education about antithyroid medication is that taking:

excessive or unnecessary antithyroid medication may produce serious or life-threatening manifestations of toxicity. Explanation: The FDA has issued a BLACK BOX WARNING regarding the use of thyroid hormones for the treatment of obesity or weight loss, either alone or with other therapeutic agents. Significant and serious complications may develop in euthyroid individuals talking thyroid hormones.

A nurse is caring for a client with subacute lymphocytic thyroiditis. The health care provider prescribes thyroid hormones to the client. From which sign during ongoing assessment should the nurse conclude that the client is responding to the therapy?

increased appetite Explanation: The nurse should observe for signs of therapeutic responses, which include increased appetite, weight loss, mild diuresis, an increased pulse rate, and decreased puffiness of the face, hands, and feet. The nurse need not observe swollen neck, excessive sweating, or heat intolerance as signs of responding to therapy. Swollen neck, sore throat, and cough may occur after two to three days of administering radioactive iodine. Sweating and flushing are the adverse reactions to thyroid hormones.

A nurse is teaching a client about a prescribed thyroid supplement and describes a drug that is relatively inexpensive, requires once-a-day dosing, and has a more uniform potency than do other thyroid hormone replacement drugs. Which drug is the nurse describing?

levothyroxine Explanation: Levothyroxine is the drug of choice for hypothyroidism because it is relatively inexpensive, requires once-a-day dosing, and has a more uniform potency than do other thyroid hormone replacement drugs. Propylthiouracil and methimazole are used to treat hyperthyroidism and are given in 8-hour intervals. Liotrix is used to treat hypothyroidism, given once a day, however, it is more expensive and does not have a more uniform potency.

A nurse is preparing to administer a scheduled dose of levothyroxine to an elderly client who is being treated in the hospital for a respiratory infection. Prior to administering the drug, the nurse should perform what assessment?

measurement of blood pressure Explanation: In older adults receiving levothyroxine, regular monitoring of blood pressure and pulse is essential. Temperature, pupillary response, and chest auscultation are not necessary before safe administration of this medication.

Based on the nurse's knowledge about thyroid hormone supplements, the nurse administers levothyroxine cautiously to a client who has recently had which condition or disorder?

myocardial infarction Explanation: A nurse should be cautious not to administer levothyroxine to a client who has recently had a myocardial infarction. Drug interactions with oral antidiabetics and insulin with hormone supplements can cause hyperglycemia. Seizure and cataract surgery are not contraindicated with the use of levothyroxine.

The nurse should teach clients who are taking thyroid hormones to take the medication:

on an empty stomach. Explanation: hyroid hormones are administered once per day, early in the morning and preferably before breakfast. An empty stomach increases the absorption of the drug.

A patient with hypothyroidism is at increased risk for respiratory depression and myxedema coma if given what category of drugs?

opioid analgesics Explanation: Most drugs given to patients with hypothyroidism have a prolonged effect, because drug metabolism in the liver is delayed and the glomerular filtration rate of the kidneys is decreased. People with hypothyroidism are especially likely to experience respiratory depression and myxedema coma with opioid analgesics and other sedating drugs. These drugs should be avoided when possible.

A hospital client's current medication administration record specifies oral administration of propylthiouracil (PTU) every 8 hours. What sign or symptom may have originally prompted the care provider to prescribe this drug?

persistent tachycardia Explanation: Propylthiouracil (PTU) is used for the treatment of hyperthyroidism; one of the characteristic symptoms of this disease is tachycardia. Tinnitus, visual disturbances, and hypotension are not associated with hyperthyroidism.