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4.10: Alpha-2 Antagonists

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    24251
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    Clonidine is an Alpha-2 antagonist.

    Mechanism of Action: Clonidine reduces sympathetic outflow from the central nervous system and decreases peripheral resistance and renal vascular resistance.

    Indications: Clonidine is used to treat hypertension (HTN) and attention deficit hyperactivity disorder (ADHD).

    Nursing Considerations: Monitor blood pressure and pulse rate frequently. Dosage is usually adjusted to the patient’s blood pressure and can cause hypotension, bradycardia, and sedation. Rebound hypertension may occur if stopped abruptly.

    Patient Teaching & Education: Patients should be taught the importance of adhering to the same dosing schedule each day. Patients may experience orthostatic blood pressure changes and should be cautioned against the use of alcohol while taking this medication. Additionally, patients may experience increased susceptibility to blood pressure changes when exercising and exposed to hot environments. If the patient experiences mental depression as a side effect of the medication, a different medication therapy may be needed.[1]

    Now let’s take a closer look at the medication grid on clonidine in Table 4.10.[2]

    Table 4:10 Cloinidine Medication Grid

    Class/Subclass

    Prototype/Generic

    Administration Considerations

    Therapeutic Effects

    Side/Adverse Effects

    Alpha-2 agonist clonidine Monitor blood pressure and pulse rate frequently

    Dosage is usually adjusted to patient’s BP and tolerance

    Treat hypertension or ADHD Hypotension

    Bradycardia

    Sedation

    Rebound hypertension if stopped abruptly

    Alpha-2 Antagonists

    A2 antagonists are used in research with limited clinical application.[3]


    1. uCentral from Unbound Medicine. https://www.unboundmedicine.com/ucentral
    2. This work is a derivative of Daily Med by U.S. National Library of Medicine in the public domain. ↵
    3. This work is a derivative of Daily Med by U.S. National Library of Medicine in the public domain. ↵

    This page titled 4.10: Alpha-2 Antagonists is shared under a CC BY 4.0 license and was authored, remixed, and/or curated by Ernstmeyer & Christman (Eds.) (OpenRN) via source content that was edited to the style and standards of the LibreTexts platform; a detailed edit history is available upon request.

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