Description
Patanol was launched in the US for use in allergic conjunctivitis. It can be
prepared in five steps from the sodium salt of phydroxyphenylacetic acid methyl ester
with phthalide. It has a fast onset of action with a long duration of action (due to slow
dissociation kinetics) that combines the ability to prevent human conjunctival mast cell
mediator release with selective H1-receptor antangonistic activity (greater H3:H1
selectivity than H2:H1 selectivity). In addition, Patanol had no inhibition of 5-
lipoxygenase, PAF acetyltransferase and thromboxane synthase while interfering with
phospholipase A2. It has a presynaptic inhibition of tachykinin release and inhibits
bronchial sensory nerves through activation of small conductance calcium activated
potassium channels. It was more potent than ketotifen and terfenadine and was
effective at inhibition of PAF, LTC4 induced conjunctivitis and TXB2 production. It does
not accumulate in the CNS, has a low affinity for H1-receptors in the brain, and
significantly inhibits allergen induce sneezing. Patanol was more effective in
conjuctival than in corneal or the trabecuiar meshwork cells.
Chemical Properties
White Solid
Originator
Kyowa Hakko (Japan)
Uses
antiallergic, antihistaminic;histamine H1 antagonist
Uses
Dual acting histamine H1-receptor antagonist and mast cell stabilizer. Antiallergic; antihistaminic.
Uses
Olopatadine hydrochloride is a potent, selective antagonist of the H1 histamine receptor (Ki = 16-41.1 nM), with much lower affinities for the H2 and H3 receptors (Ki = 43.4 and 172 μM, respectively). It blocks histamine-induced phosphoinositide turnover in isolated cells (IC50 = 9.5-39.9 nM) and prevents passive cutaneous anaphylaxis in rats (ED50 = 49 μg/kg) and anaphylactic bronchoconstriction in guinea pigs (ID50 = 30 μg/kg). Olopatadine is effective in treating allergic rhinitis and conjunctivitis. It also suppresses itch in patients with well-controlled chronic urticaria. In humans, this antihistamine does not cause cognitive or psychomotor impairment at therapeutic doses.[Cayman Chemical]
Uses
urinary antispasmodic
Definition
ChEBI:Olopatadine hydrochloride is a dibenzooxazepine.
Preparation
Olopatadine hydrochloride can be prepared in five steps from the sodium salt of phydroxyphenylacetic acid methyl ester with phthalide.
Brand name
Patanol (Alcon).
Pharmacokinetics
Olopatadine hydrochloride was launched in the US for use in allergic conjunctivitis. It has a fast onset of action with a long duration of action (due to slow dissociation kinetics) that combines the ability to prevent human conjunctival mast cell mediator release with selective H1-receptor antangonistic activity (greater H3:H1 selectivity than H2:H1 selectivity). In addition, Olopatadine hydrochloride had no inhibition of 5-lipoxygenase, PAF acetyltransferase and thromboxane synthase while interfering with phospholipase A2. It has a presynaptic inhibition of tachykinin release and inhibits bronchial sensory nerves through activation of small conductance calcium activated potassium channels. It was more potent than ketotifen and terfenadine and was effective at inhibition of PAF, LTC4 induced conjunctivitis and TXB2 production. It does not accumulate in the CNS, has a low affinity for H1-receptors in the brain, and significantly inhibits allergen induce sneezing. Olopatadine hydrochloride was more effective in conjuctival than in corneal or the trabecuiar meshwork cells.
Veterinary Drugs and Treatments
Olopatadine HCl is a selective H1 receptor antagonist and inhibitor
of histamine release from mast cells. It is marketed for topical use
to alleviate symptoms of allergic conjunctivitis in humans and is
thought to be safe for use in children three years of age and older.
Olopatadine, upon topical application in humans, was shown to
have very limited systemic absorption. It was detectable in the milk
of nursing rats, after topical application, and like most medications
should be avoided in pregnant or nursing animals.
