Autacoids (Prostanoids analogues) Flashcards
Misoprostol (prostanoid & therapeutic use)
→ PGE1 analogue
* Used in peptic ulcer, due to its GI Cytoprotective effects
(1- reduce gastric acid secretion
2- stimulate mucus synthesis
3- bicarbonate production)
* Inducing labor & medical abortion due to its oxytocic properties
(it’s combined with mifepristone (an anit-progestine) to terminate early pregnancy, given intravaginal or systemically).
* Used to protect the mucosal lining of the stomach during chronic NSAID treatment (combined with NSAIDs to decrease/prevent the incidence of NSAID-induced gastric ulcers).
-Ex: A combination product containing misoprostol and the NSAID diclofenac.
Misoprostol side effects
- Diarrhea & Abdominal pain.
- It’s an abortifacient; contraindicated during pregnancy (Category X)
Lubiprostone (prostanoid & therapeutic use)
→ PGE1
* Constipation (act as laxative): It stimulates chloride channels in the luminal cells of the intestinal epithelium → increasing intestinal fluid secretion.
* Indicated for the treatment of:
(1) chronic idiopathic constipation
(2) opioid-induced constipation
(3) IBS-C
Lubiprostone side effects
- Most common: Nausea & diarrhea
(↓ Nausea if taken with food) - Colicky cramps
Alprostadil (prostanoid & therapeutic use)
PGE1
* 2nd line treatment for erectile dysfunction: Given as intra-cavernous injection (directly into corpus cavernosum) or urethral suppository (into urethra) → Causes vasodilatation in corpus cavernosum → Enhances penile erection
* To maintain the patency of ductus arteriosus in neonates with congenital heart disease prior to surgical correction (Normally, duct closes soon after delivery to allow normal blood circulation between the lungs and heart, but in some cases we need to keep it opened)
Alprostadil side effects
Penile pain
Dinoprostone (prostanoid & therapeutic use)
→ PGE2
* Inducing labor near full term.
* Administred as vaginal suppository for Inducing medical abortion (2nd trimester of pregnancy)
Cabroprost (prostanoid & therapeutic use)
→ PGF2
* Used by intra-amniotic for Induction of labor
* Given IM for the controlling of postpartum hemorrhage when there is no response to the usual therapy (IV oxytocin, uterine massage, IM ergot alkaloide).
Cabroprost side effects
- Anaphylactic shock & cardiovascular collapse
- Vomiting and diarrhea
Bimatoprost & Latanoprost (prostanoid & therapeutic use)
→ PGF2
* Latanoprost: A stable long-acting PGF2a derivative, it was the first prostanoid used for glaucoma.
* Bimatoprost: FDA approved for treatment of eyelash hypotrichosis and has shown efficacy in enhancing eyelash growth after chemotherapy.
- Treatment of open-angle glaucoma: Administered as ophthalmic solutions to decrease the intraocular pressure (they are as effective as timolol or better in reducing intraocular pressure).
- Have cosmetic effect in the treatment of Hypotrichosis (reduced hair growth).
Bimatoprost & Latanoprost side effects
- Drying of eyes
- Conjunctivitis
- Red eye (congested eye)
- Irreversible brown pigmentation of iris and eyelashes
- Darkening of eyelid skin due to increased melanin production that is reversible with discontinuation (common but minor S/E)
Epoprostenol (prostanoid & therapeutic use)
→ PGI2
* Given IV
* Prevent platelet aggregation → Used during hemodialysis & Open-heart surgery.
* For pulmonary arterial hypertension (PAH): because it causes
(1) direct vasodilatation of pulmonary & systemic arterial vascular beds
(2) reduction in pulmonary arterial resistance with a subsequent increase in cardiac index and oxygen delivery.
Epoprostenol side effects
- Flushing
- Headache
- Hypotension
- Nausea & Diarrhea
Iloprost (prostanoid & therapeutic use)
→ PGI2
* For pulmonary arterial hypertension (Given oral / inhalation (frequent doses) / Subcutaneous)
Treprostinil (prostanoid & therapeutic use)
→ PGI2
* For pulmonary arterial hypertension (Given IV / subcutaneous / inhalation)
