Autacoid Drugs Flashcards
Histamine H1 receptor antagonists (group) - MoA
Contain an alkylamine group that resembles the side chain of histamine and permits them to bind to the H1 receptor and act as competitive receptor antagonists, and block most of the effects of histamine on vascular smooth muscles and nerves and thereby prevent or counteract allergic reactions
Histamine H1 receptor antagonists (group) - Clinical use
Allergic reactions (all are equally active for this), but differ markedly in their sedative, antiemetic and anticholinergic properties.
Histamine H1 receptor antagonists (group) - Interactions
Extensively metabolized by cytochrome P450.
1st generation antihistamines
Chlorpheniramine Clemastine Dimenhydrinate Diphenhydramine Hydroxyzine Meclizine Promethazine Doxepin Doxylamine with vitamin B6
1st generation antihistamines - MoA
Block cholinergic muscarinic receptors
1st generation antihistamines - Clinical use
Used to produce sedation
Treat: Nausea, vomiting, vertigo.
Prevention of motion sickness.
1st generation antihistamines - Administration and Contraindication (Caution)
Administered oral or parenteral
Caution for treatment of children
1st generation antihistamines - Adverse effects
Sedation Children and infants: cause excitement Dry mouth Blurred vision Tachycardia Urinary retention Hallucinations
Chlorpheniramine - Clinical use
Allergic reactions to pollen, mold, and other environmental allergens
Dimenhydrinate, Meclizine - Clinical use
Vertigo
Prevent motion sickness
Diphenhydramine, Hydroxyzine, Promethazine - Clinical use
Induce sleep, pre-op sedation.
Distress from severe pruritus
Doxepin - Clinical use
Antidepressant and anxiolytic effects
Insomnia treatment (low doses)
Induce sleep, preoperative sedation
Distress from severe pruritus
Doxylamine - Clinical use
With vitamin B6 for morning sickness in pregnant women
Which 1st generation antihistamines must be cautiously used against heavy machinery in patients taking the drug
Diphenhydramine
Hydroxyzine
Promethazine
Doxepin
2nd generation antihistamines + administration
Cetirizine Fexofenadine Loratadine Desloratadine Astemizole (Removed from market) Terfenadine (Removed from market)
Oral or parenteral
2nd generation antihistamines - Clinical use
Cause little or no sedation and are preferred for the treatment of allergic reactions
Lack antiemetic activity
Does 2nd generation antihistamines cross BBB?
No
Which 2nd generation antihistamine can cause some sedation?
Cetrizine
Intranasal antihistamine
Azelastine
Azelastine - Clinical use
Allergic rhinitis
Azelastine - Interaction and Contraindication (Caution)
Metabolized by cytochrome P450 enzymes to active metabolite, desmethylazelastine.
Caution against heavy machinery in patients taking the drug
Azelastine - Adverse effects
Rare: Dizziness Drowsiness Headache Fatigue Nasal irritation Dry mouth Weight gain
Ophthalmic antihistamines
Levocabastine
Epinastine
Olopatadine
Ketotifen
Ophthalmic antihistamines - Clinical use
Temporary relief of symptoms of conjunctivitis
Levocabastine, Epinastine, Olopatadine - MoA
Selective H1 antagonist
Ketotifen - MoA
Selective, noncompetitive H1 antagonist and mast cell stabilizer
Levocabastine, Epinastine, Olopatadine - Clinical use
Seasonal allergic conjunctivitis
Ketotifen - Clinical use
Prevention of itching of the eye in allergic conjunctivitis
Ophthalmic antihistamines - Adverse effects
Transient stinging & burning of eyes
Serotonin agonists
Buspirone Sumatriptan Triptans Ergot drugs Cisapride (Removed from market) Tegaserod (Removed from market) Lorcaserin Flibanserin
Which serotonin agonist is a partial agonist?
Buspirone
Buspirone - MoA
Acts at 5-HT1A receptor
Buspirone - Clinical use
Anxiety
Depression
Sumatriptan (Triptans), Ergot drugs - MoA
Acts at 5-HT1D/1B receptor
Sumatriptan (Triptans), Ergot drugs - Clinical use
Migraine headaches
Lorcaserin - MoA
Act at 5-HT2C receptor (activates these receptors on POMC neurons located in the hypothalamus and leads to decreased food intake and promote fullness)
Lorcaserin - Clinical use
Obesity
Flibanserin - MoA
Acts at 5-HT1A receptor agonist and Acts at 5-HT2A receptor antagonist
Flibanserin - Clinical use
Premenopausal women with hypoactive sexual desire disorder.
Flibanserin - Adverse effects
Severe syncope when taken with alcohol, in individuals with hepatic dysfunction, and with certain other drugs that inhibit Flibanserin metabolism
When can Tagaserod be used?
EMERGENCIES
Serotonin antagonists
Clozapine, Cyproheptadine, Methysergide,
Setrons (Ondansetron, Ganisetron, Alosetron, Palonosetron, Dolasetron)
Clozapine - MoA
Partially blockade of 5-HT2 receptors in CNS
Clozapine - Clinical use
Schizophrenia
Cyproheptadine - MoA
5-HT2 receptor antagonist with H1 antihistamine activity
Cyproheptadine - Clinical use
Urticaria,
allergic reactions with pruritus,
Carcinoid tumor (with opioid antidiarrheal)
Cyproheptadine- Adverse
Slight to moderate drowsiness
Methysergide- MoA
5-HT2 receptor antagonist
Methysergide - Clinical use
Prevent migraine headaches
Setrons - MoA
Selective 5-HT3 receptor antagonist.
Prevents vomiting & nausea by blocking serotonin in chemoreceptor trigger zone and vagal afferent nerves in GI
Setrons - Clincal use
Ondansetron and Ganisetron: Antiemetic (chemo and radiation therapy),
Alosetron: Women with IBS with diarrhea
Palonosetron: Prevention of acute or delayed nausea and vomiting after emetogenic cancer chemotherapy
Dolasetron: Pre-op emesis
Serotonin reuptake inhibitors - Clinical use
Depression & CNS disorders
Eicosanoid synthesis inhibitors
Leukotriene inhibitors, NSAIDs, Corticosteroids
Leukotriene inhibitors - MoA
Inhibition of 5-lipoxygenase OR blocking leukotriene receptors
NSAID - MoA
Inhibition of cyclooxygenase & prostaglandin synthesis
Corticosteroids - MoA
Block formation of all eicosanoids by inhibition of phospholipase A2
Leukotriene inhibitors - Clinical use
Asthma
NSAIDs - Clinical use
Pain and inflammation
Corticosteroids - Clinical use
Antiinflammatory, Antiallergic, Antineoplastic,
Adrenal and nonadrenal disorders
Prostaglandin E1 + derivatives
Alprostadil
Misoprostol
Misoprostol - MoA
Local effect on GI mucosa, cytoprotective: inh of gastric acid secretion, increases bicarbonate secretion
Alprostadil - Clinical use
Maintain patent ductus arteriosis
Erectile dysfunction when other drugs are contraindicated.
Alprostadil - Adverse effects
Erectile dysfunction: penile pain, fibrosis, priapism (persistent erection), flushing, diarrhea, headache, fever
Misoprostol - Clinical use
Prevention of NSAID-induced gastric and duodenal ulcers
Abortifacient: combo with mifepristone (progesterone antagonist)
Misoprostol - contraindication
Pregnancy
Misoprostol - Adverse effects
Diarrhea (minimized with gradual increase of the dose).
Uterine contractions and premature labor
Prostaglandin E2 and F2 alpha + derivatives
Dinoprostone
Carboprost
Latanoprost
Bimatoprost, travoprost and tafluprost
Dinoprostone and Carboprost - MoA
Oxytocic activity and increased uterine contractions in pregnancy
Latanoprost - MoA
Acts on FP receptors to increase aqueous humor outflow via the uveoscleral pathway
Bimatoprost and travorpost - MoA
FP receptor agonists
Dinoprostone - Clinical use
Cervical ripening before labor induction (vaginal instert, gel), Evacuate uterine contents (supp)
Carboprost - Clincal use:
Postpartum bleeding (that is resistant to other drugs) Abortifacient
Carboprost - Adverse effect
Flushing, diarrhea, vomiting, altered blood pressure, blurred vision, resp distress.
Latonoprost - Clincal use
Open angle glaucoma (that is resistant to other drugs)
Latonoprost - Adverse effect
Permanent eye color change (increases melanin)
Bimatoprost and travoprost - Clinical use
Open angle glaucoma, ocular hypertension
Prostaglandin I2 + derivatives
Epoporstenol
Treprostinil
Epoprostenol – MoA
Acts on IP receptors to dilate pulmonary blood vessels and increase pulmonary blood flow
Epoprostenol and Treprostinil - Clinical use
Pulmonary arterial hypertension (reduce symptoms associated with exercise)
Epoprostenol - Adverse effects
Flushing, tachycardia, hypotension, diarrhea, nausea, vomiting, flulike symptoms
Endothelin-1 antagonists
Bosentan
Ambrisentan
Macitentan
Endothelin-1 antagonists - Clinical use
Pulmonary arterial hypertension
Bosentan - Contraindication
Pregnancy, women in childbearing age not on hormonal contraceptives
Bosentan - Adverse effects
Elevated aminotransferase levels. Birth defects (animal studies)
Sildenafil - Classification
PDE5 inhibitor
Sildenafil - MoA
Increases cyclic guanosine monophosphate within pulmonary vascular smooth muscle cells, results in relaxation and vasodilation of the pulmonary vascular bed
Sildenafil - Clinical use
Pulmonary arterial hypertension
Sexual dysfunction
Clemastine - Clinical use
Allergic rhinitis, Hay fever, pruritus