Yellow Fever Vaccine Yellow Fever Vaccine (YFV‑17D) is a live‑attenuated virus vaccine that confers long‑lasting immunity against yellow fever virus infection. It is the reference standard used worldwide for travelers, residents of endemic areas, and for outbreak control. — Mechanism of Action Live‑attenuated YFV‑17D enters host cells via endocytosis, primarily infecting dendritic cells and macrophages … Read more
Ycanth Mechanism of Action Ycanth is a novel irreversible P2Y12 receptor antagonist that blocks ADP‑mediated platelet activation. Inhibits the binding of ADP to surface P2Y12 receptors on platelets, preventing the formation of the GPIIb/IIIa affinity layer. Suppresses platelet aggregation and thrombus formation in arterial circulation. Provides rapid onset of action without the need for hepatic … Read more
Yaz Yaz is a combined oral contraceptive (COC) containing drospirenone (3 mg) and ethinyl estradiol (0.02 mg). It is marketed for contraception and for the management of hormonally driven disorders such as acne, pre‑menstrual dysphoric disorder (PMDD), and moderate menstrual bleeding. — Mechanism of Action Ovulation suppression – Drospirenone antagonizes LH and FSH surge, preventing follicular rupture. … Read more
Yasmin Yasmin is a combined oral contraceptive (COC) comprising ethinyl estradiol (EE) 0.0125 mg and drospirenone 3.5 mg per tablet. It provides reliable contraception while also offering therapeutic benefits for menstrual and hormonal disorders. Mechanism of Action Estrogen component (EE): Suppresses luteinizing hormone (LH) and follicle‑stimulating hormone (FSH) release → prevents follicular maturation and ovulation. Enhances endometrial … Read more
Xyzal Cetirizine hydrochloride – a non‑sedating, second‑generation H1 receptor antagonist. — Mechanism of Action Selective antagonist of peripheral histamine H1 receptors → blocks H1‑mediated vasodilation, vascular permeability, and smooth‑muscle contraction. Minimal central nervous system penetration → negligible blockade of brain H1 receptors → low sedation risk. Inhibits the degranulation of mast cells and basophils, reducing … Read more
Xyrem Xyrem (sodium oxybate), the salt form of gamma‑hydroxybutyrate (GHB), is a schedule‑IV CNS depressant used primarily for the treatment of cataplexy, excessive daytime sleepiness, and disrupted nighttime sleep in narcolepsy patients. Mechanism of Action Sodium oxybate is a short‑acting centrally acting neurotoxin that: Binds preferentially to GABAB receptors (primary site of action) and, at … Read more
Xyosted Xyosted is a novel, orally bioavailable selective inhibitor of the oncogenic BRAF V600E mutation used primarily in metastatic melanoma. Mechanism of Action Selective ATP‑competitive inhibition of BRAF V600E reduces aberrant MAPK/ERK signaling, leading to decreased cell proliferation and increased apoptosis in BRAF‑mutant tumor cells. Minimal activity against wild‑type BRAF, limiting off‑target kinase inhibition. Potent … Read more
Xylocaine Jelly Xylocaine Jelly (lidocaine hydrochloride 2 % topical preparation) is a non‑systemic local anesthetic used for pain relief in mucocutaneous sites. Mechanism of Action Selectively blocks voltage‑gated Na⁺ channels on neuronal membranes, inhibiting depolarization. The high concentration of lidocaine in the jelly saturates surface receptors, producing a reversible, local anesthetic effect within seconds. No significant … Read more
Xylocaine Xylocaine (generic lidocaine) is a widely used short‑acting local anesthetic and class Ib antiarrhythmic. It blocks voltage‑gated Na⁺ channels, inhibiting nerve impulse conduction and cardiac depolarization. Mechanism of Action Na⁺ Channel Blockade Binds preferentially to the inactivated state of the sodium channel. Prevents rapid sodium influx → ↓ depolarization rate. Reversible Inactivation Rapidly equilibrates between … Read more
Xylitol Xylitol is a five‑carbon sugar alcohol (polyol) used mainly as a low‑calorie sweetener and for dental caries prevention. It is also employed in pharmaceutical formulations (sprays, lozenges, syrups) and as an excipient. Mechanism of Action Inhibits cariogenic bacterial metabolism: Xylitol cannot be fermented by Streptococcus mutans; it is transported into the bacterial cell via … Read more