Hypothalamic Agents

Hypothalamic Agents: Generic and Brand Names

Here is a table of commonly encountered endocrine system drugs, their generic names, and brand names:

Classification	Generic Name	Brand Name
Agonists	goserelin	Zoladex
	histrelin	Vantas
	leuprolide	Lupron
	nafarelin	Synarel
	tesamorelin	Egrifta
Antagonists	degarelix
Antagonists	ganirelix	Antagon

Therapeutic Action

The desired and beneficial action of hypothalamic agents is:

Not clearly identified as there are only minute quantities found.
Not all of them are used as pharmacological agents. Some are used for diagnostic purposes only and others are primarily used as antineoplastic agents.
Tesamorelin is used to stimulate GH and its lipolytic effects, helping to decrease the excess abdominal fat in HIV-infected patients with lipodystrophy.

Indications

Hypothalamic agents are indicated for the following medical conditions:

Hypothalamic hormones are not all available for pharmacological use; those that are available are used mostly for diagnostic testing, for treating some forms of cancer, or as adjuncts in fertility programs.
Agonists like goserelin, histrelin, leuprolide, and nafarelin are analogues of GnRH. They decrease production of sex hormones. They are used as treatment for precocious puberty, endometriosis, and advanced prostate cancer.
Antagonists of GnRH like degarelix and ganirelix are used as treatment for advanced prostate cancer and inhibition of premature LH surge in women undergoing controlled ovarian stimulation for fertility.

Here are some important aspects to remember for indication of hypothalamic agents in different age groups:

Children

Monitor closely for adverse effects associated with changes in overall endocrine function, particularly growth and development and metabolism.
Standard part of treatment plan should include periodic radiograph of long bones and monitoring of blood sugar and electrolytes.

Adults

Monitor blood sugar and electrolytes.
Review proper administration of nasal forms of drugs for diabetes insipidus to prevent complications.
Review proper storage, preparation, and administration of regular injections.
Drugs should not be used among pregnant and lactating women unless benefits clearly outweigh the risks.

Older adults

Evaluate hydration, nutrition, and electrolyte balance periodically.
Review proper administration technique because they are at high risk for dehydrated membranes and ulcerations.

Pharmacokinetics

Here are the characteristic interactions of hypothalamic agents and the body in terms of absorption, distribution, metabolism, and excretion:

Contraindications and Cautions

The following are contraindications and cautions for the use of hypothalamic agents:

Allergy to any component of the drug. To prevent hypersensitivity reactions.
Peripheral vascular disorders. Can alter absorption of drugs.
Rhinitis. Alters absorption of nafarelin nasal spray.
Renal or hepatic impairment. Interfere with drug metabolism and excretion.
Pregnancy or lactation. Potential adverse effects to fetus or neonates.

Adverse Effects

Use of hypothalamic agents may result to these adverse effects:

Agonists: increased release of sex hormones, ovarian overstimulation, flushing, increased temperature and appetite, fluid retention
Antagonists: decreased testosterone level, loss of energy, decreased sperm count and activity, alterations in secondary sex characteristics (decrease in female sex hormones, amenorrhea), fluid and electrolyte changes, insomnia, irritability

Interactions

Drug interactions of hypothalamic agents are related to the specific hormones that the drug is affecting. They will be discussed in detail as each agents for specific hormones will be covered in this study guide.

Nursing Considerations

The specific nursing care of patient who is receiving hypothalamic releasing factor is related to the hormone(s) that the drug is affecting. This will be discussed further as each drugs affecting certain hormones will be covered in this study guide.

Practice Quiz: Hypothalamic Agents

Here are some practice questions for this study guide. Please visit our nursing test bank page for more NCLEX practice questions.

1. All of these drugs can decrease the production of sex hormones, except:

A. goserelin
B. histrelin
C. degarelix
D. tesamorelin

1. Answer: C. degarelix

Options A, B, and D are all hypothalamic agonists and can, therefore, decrease the production of sex hormones. Agonists inhibit pituitary gonadotropin secretion, with a resultant drop in the production of sex hormones.

2. Which of the following health history data will alert the nurse to question the use of hypothalamic agents in a short-term therapy?

A. history of hepatic lobe transplant three years ago
B. a mother who practices mixed feeding to her newborn baby
C. a chest x-ray suggestive of pneumonia
D. fever probably caused by post-surgical wound infection

2. Answer: B. a mother who practices mixed feeding to her newborn baby

Hypothalamic agents should be cautioned in lactating mothers because of potential adverse effects to the neonate. All other options are not contraindicated.

References and Sources

References and sources for this pharmacology guide for Hypothalamic Agents:

Karch, A. M., & Karch. (2011). Focus on nursing pharmacology. Wolters Kluwer Health/Lippincott Williams & Wilkins. [Link]
Katzung, B. G. (2017). Basic and clinical pharmacology. McGraw-Hill Education.
Lehne, R. A., Moore, L. A., Crosby, L. J., & Hamilton, D. B. (2004). Pharmacology for nursing care.
Smeltzer, S. C., & Bare, B. G. (1992). Brunner & Suddarth’s textbook of medical-surgical nursing. Philadelphia: JB Lippincott.

Route	Onset	Peak	Duration
IM depot	4 h	Variable	1,2,3, or 4 mo
T1/2: 3 h Metabolism: unknown Excretion: unknown