COUGH-DECONGESTANTS Flashcards
What do decongestants specifically treat
,Sinus and nasal congestion
What are decongestants
,They are adrenergic agonists (sympathomimetics) that stimulate alpha 1-adrenergic receptors to constrict blood vessels, thereby reducing sinusoid vessel engorgement and mucosal edema.
Alpha adrenergic receptor decongestants, also known as nasal decongestants, bind to alpha-1 adrenergic receptors in the blood vessels of the nasal mucosa. This binding causes vasoconstriction, which means the blood vessels narrow, leading to reduced blood flow and decreased swelling in the nasal passages. This helps relieve congestion and improves airflow through the nasal passages. Common examples of alpha adrenergic receptor decongestants include drugs like pseudoephedrine and phenylephrine, which are often found in over-the-counter cold and sinus medications.
How many types of decongestants are available
,Three types of decongestants are available.
What are direct-acting decongestants
,Direct-acting decongestants (e.g., phenylephrine, oxymetazoline, tetrahydrozoline) bind directly to adrenergic receptors.
How do indirect-acting decongestants work
,Indirect-acting decongestants (e.g., ephedrine) displace norepinephrine from storage vesicles in prejunctional nerve terminals, and tachyphylaxis )Tachyphylaxis trong tiếng Việt có thể được dịch là “sự giảm đáng kể về tác dụng sau một thời gian sử dụng liên tục” hoặc “sự chế tác nhanh”. Đây là hiện tượng mà cơ thể trở nên ngày càng không phản ứng mạnh mẽ hoặc không phản ứng nữa với một chất hoặc tác nhân sau khi đã sử dụng nhiều lần hoặc liên tục trong thời gian dài.)can develop as stored neurotransmitter is depleted.
used to relieve nasal congestion by affecting the sympathetic nervous system. They work by stimulating the release of norepinephrine, a neurotransmitter, which leads to vasoconstriction (narrowing of blood vessels) in the nasal passages. This narrowing of blood vessels reduces swelling and congestion in the nasal tissues, allowing for improved airflow. sử dụng để giảm ngứa mũi bằng cách ảnh hưởng đến hệ thần kinh giao cảm. Chúng hoạt động bằng cách kích thích sự giải phóng của norepinephrine, một chất truyền thần kinh, dẫn đến co mạch (co rút các mạch máu) trong đường hô hấp. Việc co mạch này làm giảm sưng và ngứa trong các mô mũi, cho phép dòng không khí được cải thiện.
Unlike direct-acting decongestants that bind directly to specific receptors on blood vessels to cause vasoconstriction, indirect-acting decongestants work by affecting the release and availability of norepinephrine, which then leads to the desired constriction of blood vessels. Khác với các loại thuốc giảm ngứa tác động trực tiếp kết hợp trực tiếp vào các receptor cụ thể trên mạch máu để gây co mạch, thuốc giảm ngứa tác động gián tiếp hoạt động bằng cách ảnh hưởng đến việc giải phóng và khả năng tiếp cận của norepinephrine, sau đó dẫn đến sự co mạch mong muốn của các mạch máu.
What are mixed decongestants
,Mixed decongestants (e.g., pseudoephedrine) have both direct and indirect activity.
How are systemic decongestants metabolized in the body
,Systemic decongestants are rapidly metabolized by monoamine oxidase (MAO) and catechol-O-methyltransferase in the gastrointestinal (GI) mucosa, liver, and other tissuesSystemic decongestants, such as pseudoephedrine and phenylephrine, are metabolized in the body primarily by the liver. After being absorbed into the bloodstream from the gastrointestinal tract, these decongestants are carried to the liver, where various enzymes work to break them down into metabolites that can be eliminated from the body.
Pseudoephedrine undergoes extensive metabolism in the liver, primarily through a process called oxidation. It is converted into its main metabolite, norpseudoephedrine (also known as cathine), which is less potent but still has some vasoconstrictive effects.
Phenylephrine is also metabolized in the liver through processes like glucuronidation and sulfation. These metabolic pathways involve attaching specific molecules (glucuronic acid or sulfate) to the phenylephrine molecule, making it more water-soluble and easier to excrete by the kidneys.
The resulting metabolites are eventually eliminated from the body through the urine. The rate of metabolism and elimination can be influenced by factors such as liver function, age, genetics, and the presence of other medications or substances that may interact with the metabolic pathways.
What is the oral bioavailability of phenylephrine
,Phenylephrine has a low oral bioavailability, approximately 38%.
How long is the half-life of pseudoephedrine
,The half-life of pseudoephedrine is 6 hours.
How long is the half-life of phenylephrine
,The half-life of phenylephrine is 2.5 hours.
When do peak concentrations for both pseudoephedrine and phenylephrine occur after oral administration
,Peak concentrations for both drugs are reached at 0.5–2 hours after oral administration.
What are some cardiovascular adverse effects associated with decongestants
,Cardiovascular adverse effects include elevated blood pressure, tachycardia, palpitations, or arrhythmias.
Các tác động phụ về tim mạch bao gồm tăng huyết áp, nhịp tim nhanh, rung tim hoặc loạn nhịp.
What are some CNS adverse effects associated with decongestants
,CNS adverse effects include restlessness, insomnia, anxiety, tremors, fear, or hallucinations.
Các tác động phụ về hệ thần kinh trung ương bao gồm sự bồn chồn, mất ngủ, lo âu, rung động, sợ hãi hoặc ảo giác.
Which age groups are more likely to experience adverse effects from decongestants
,Children and older adults are more likely to experience adverse effects compared to other age groups.
Why are adverse effects more common with systemic decongestants
,Adverse effects are more common with systemic decongestants because topical decongestants are minimally absorbed.
