Cetirizine¿¡ ´ëÇÑ Mechanism_Of_Action Á¤º¸ Cetirizine competes with histamine for binding at H1-receptor sites on the effector cell surface, resulting in suppression of histaminic edema, flare, and pruritus. The low incidence of sedation can be attributed to reduced penetration of cetirizine into the CNS as a result of the less lipophilic carboxyl group on the ethylamine side chain. Pseudoephedrine¿¡ ´ëÇÑ Mechanism_Of_Action Á¤º¸ Pseudoephedrine acts directly on both alpha- and, to a lesser degree, beta-adrenergic receptors. Through direct action on alpha-adrenergic receptors in the mucosa of the respiratory tract, pseudoephedrine produces vasoconstriction. Pseudoephedrine relaxes bronchial smooth muscle by stimulating beta2-adrenergic receptors. Like ephedrine, pseudoephedrine releasing norepinephrine from its storage sites, an indirect effect.
Pharmacology
Cetirizine¿¡ ´ëÇÑ Pharmacology Á¤º¸ Cetirizine, the active metabolite of the piperazine H1-receptor antagonist hydroxyzine, is used to treat chronic idiopathic urticaria, perennial allergic rhinitis, seasonal allergic rhinitis, allergic asthma, physical urticaria, and atopic dermatitis. Pseudoephedrine¿¡ ´ëÇÑ Pharmacology Á¤º¸ Pseudoephedrine is a sympathomimetic agent, structurally similar to ephedrine, used to relieve nasal and sinus congestion and reduce air-travel-related otalgia in adults. The salts pseudoephedrine hydrochloride and pseudoephedrine sulfate are found in many over-the-counter preparations either as single-ingredient preparations, or more commonly in combination with antihistamines and/or paracetamol/ibuprofen. Unlike antihistamines, which modify the systemic histamine-mediated allergic response, pseudoephedrine only serves to relieve nasal congestion commonly associated with colds or allergies. The advantage of oral pseudoephedrine over topical nasal preparations, such as oxymetazoline, is that it does not cause rebound congestion (rhinitis medicamentosa).
Protein Binding
Cetirizine¿¡ ´ëÇÑ ´Ü¹é°áÇÕ Á¤º¸ Very high (93%) plasma protein binding Pseudoephedrine¿¡ ´ëÇÑ ´Ü¹é°áÇÕ Á¤º¸ Pseudoephedrine does not bind to human plasma proteins over the concentration range of 50 to 2000 ng/mL
Cetirizine¿¡ ´ëÇÑ Absorption Á¤º¸ mean peak plasma concentration (Cmax) of 114 ng/mL at a time (Tmax) of 2.2 hours postdose was observed for cetirizine Pseudoephedrine¿¡ ´ëÇÑ Absorption Á¤º¸ Pseudoephedrine is readily and almost completely absorbed from the GI tract and there is no evidence of first-pass metabolism.
Cetirizine¿¡ ´ëÇÑ Biotransformation Á¤º¸ Not Available Pseudoephedrine¿¡ ´ëÇÑ Biotransformation Á¤º¸ Hepatic.
Toxicity
Cetirizine¿¡ ´ëÇÑ Toxicity Á¤º¸ Somnolence (sleepiness or unusual drowsiness), restlessness, irritability Pseudoephedrine¿¡ ´ëÇÑ Toxicity Á¤º¸ Common adverse reactions include nervousness, restlessness, and insomnia. Rare adverse reactions include difficult/painful urination, dizziness/lightheadedness, heart palpitations, headache, increased sweating, nausea/vomiting, trembling, troubled breathing, unusual paleness, and weakness.
Drug Interactions
Cetirizine¿¡ ´ëÇÑ Drug_Interactions Á¤º¸ Not Available Pseudoephedrine¿¡ ´ëÇÑ Drug_Interactions Á¤º¸ Alseroxylon Increased arterial pressureIsocarboxazid Increased arterial pressureLinezolid Possible increase of arterial pressureMethyldopa Increased arterial pressureBromocriptine The sympathomimetic increases the toxicity of bromocriptineTranylcypromine Increased arterial pressureMidodrine Increased arterial pressureMoclobemide Moclobemide increases the sympathomimetic effectPargyline Increased arterial pressurePhenelzine Increased arterial pressureRasagiline Increased arterial pressureReserpine Increased arterial pressureTrimipramine The tricyclic increases the sympathomimetic effectProtriptyline The tricyclic increases the sympathomimetic effectNortriptyline The tricyclic increases the sympathomimetic effectAmitriptyline The tricyclic increases the sympathomimetic effectAmoxapine The tricyclic increases the sympathomimetic effectClomipramine The tricyclic increases the sympathomimetic effectImipramine The tricyclic increases the sympathomimetic effectDesipramine The tricyclic increases the sympathomimetic effectDoxepin The tricyclic increases the sympathomimetic effectDeserpidine Increased arterial pressureGuanethidine The agent decreases the effect of guanethidine
Cetirizine¿¡ ´ëÇÑ Description Á¤º¸ A potent second-generation histamine H1 antagonist that is effective in the treatment of allergic rhinitis, chronic urticaria, and pollen-induced asthma. Unlike many traditional antihistamines, it does not cause drowsiness or anticholinergic side effects. [PubChem] Pseudoephedrine¿¡ ´ëÇÑ Description Á¤º¸ An alpha- and beta-adrenergic agonist that may also enhance release of norepinephrine. It has been used in the treatment of several disorders including asthma, heart failure, rhinitis, and urinary incontinence, and for its central nervous system stimulatory effects in the treatment of narcolepsy and depression. It has become less extensively used with the advent of more selective agonists. [PubChem]