Histamine and Serotonin - 5 Flashcards
Chemical and mechanical release
displace histamine from heparin-protein complex within cell
Immunological release
mast cell and basophil degranulation
First generation antihistamines
cause sedation, more likely to block autonomic receptors
Second generation antihistamines
less sedating, poor distribution into CNS
Mepyramine
(1st gen antihistamine) insect bite ointment
Diphenhydramine
1st gen antihistamine
-sedative in adults, causes hyperactivity in children
Doxylamine
1st gen antihistamine
decongestant - no rebound swelling
Triprolidine
1st gen antihistamine
decongestant - no rebound swelling
Brompheniramine
1st gen antihistamine
hay fever aid
Hydroxyzine
1st gen antihistamine
anxiolytic - due to antiserotonergic activity
Promethazine
1st gen antihistamine
Sedative, anti-emetic (due to CNS effects)
Cyproheptadine
1st gen antihistamine
Orexigenic (appetite stimulant) - antiserotonergic activity
Cetirizine
2nd gen antihistamine
Allergies, uticaria
Levocetirizine
2nd gen antihistamine
hay fever allergies
Loratadine
2nd gen antihistamine
hay fever, skin allergies
Desloratadine
2nd gen antihistamine
allergies
Terfenadine
2nd gen antihistamine
allergies
WITHDRAWN due to cardiotoxicity
Fexofenadine
2nd gen antihistamine
hay fever, uticaria
Cimetidine
H2 antagonist, antiandrogenic effects
used to treat peptic ulcers
Ranitidine, fimotidine, nizatidine
H2 antagonist - used to treat peptic ulcers
Cromoglicic acid
Mast cell stabilizer - blocks calcium channels needed for degranulation
-asthma, allergic rhinitis, allergic conjunctivitis
Nedocromil
Mast cell stabilizer - blocks calcium channels needed for degranulation
-asthma
5-Hydroxytryptamine
Serotonin
-neurotransmitter in CNS and enteric nervous system
5-HT1 receptors
found in CNS and some blood vessels
-neural inhibition and vasoconstriction
5-HT1D Agonists
1 trip erg in the bus -cerebral vasoconstricion triptans ergotamine busiprone
5-HT2A receptors
CNS, PNS, smooth muscle, platelets
-neuronal excitation, smooth muscle contraction, platelet aggregation, vasoconstriction.
5-HT3 receptors
anti-emetic receptors
-ligand fated channel
Serotonin Syndrome
- severe muscle rigidity, cardiovascular instability, seizures
- treated with anticonvulsants, muscle relaxants and cyproheptadine
