MISOPROSTOL PROPERTIES AND ACTION
Pharmachologic effect
Misoprostol is a synthetic analogue of prostaglandin E. It has antisecretory activity.
When taken orally (in the form of tablets) it reduces the release of hydrochloric acid, stimulates the secretion of bicarbonate and mucus, and protects the cells of internal organs. Increases the stability of the gastric mucosa and prevents the development of erosive and ulcerative lesions, promotes the healing of peptic ulcers. The action usually develops 30 minutes after administration and lasts about 3 hours.
Indications for use
Misoprostol is recommended for use with the following health issues:
- Prevention of the development of gastric ulcers associated with the use of NSAIDs.
- Treatment of exacerbation of duodenal ulcer.
- Stomach ulcer.
- In combination with the Mefiprostone, is indicated for abortion in the early stages (up to 42 days).
How does it work
Misoprostol has a weak stimulating effect on the smooth muscles of the gastrointestinal tract. It is a catalyst for the contraction of smooth muscle fibers of the myometrium and the expansion of the cervix.
Due to the ability of the drug to stimulate uterine contractions, the opening of its cervix is easier. The tone of the uterus increases, which can provoke a miscarriage.
Misoprostol has no clinically significant effect on prolactin, the level of gonadotropins, thyroid stimulating hormone, growth hormone, thyroxine, cortisol, creatinine, platelet aggregation, pulmonary function and cardiovascular system.
Contraindications
- Misoprostol is categorically contraindicated during pregnancy, as it has a teratogenic effect and is used exclusively to interrupt it. If a woman taking this drug finds out that she is pregnant, she should immediately stop using Misoprostol. If there is a suspicion of an ectopic pregnancy, it is contraindicated to use the drug.
- Hypersensitivity to the components of the drug, including other prostaglandins and their analogues.
- Lactation.
- Children and adolescents (up to 18 years).
Side effects
- From the digestive tract: abdominal pain, dyspepsia, flatulence (2.9%), nausea and / or vomiting, diarrhea (11-40%) or constipation (1.1%).
- From the genitourinary system: menstrual irregularities, dysmenorrhea, hypermenorrhea, postmenopausal vaginal spotting, menorrhagia, metrorrhagia, pain in the lower abdomen associated with contractions of the myometrium.
- Allergic reactions: skin rash, itching, anaphylactic reactions, angioedema.
- Other: changes in body weight, dizziness, headache (2.4%), asthenia, fatigue, hyperthermia, chills; extremely rarely in women in the pre- and postmenopausal period – convulsions.
Dosage and administration
Orally with water. The dosage regimen is determined individually, depending on the indications.
For the prevention of gastric ulcers caused by NSAIDs, and the treatment of erosive gastritis and peptic ulcer of the stomach and duodenum: 200 mcg 2-4 times a day (last dose – before bedtime); daily dose – 400-800 mcg. With poor tolerance, a single dose may be reduced to 100 mg. In renal failure, the daily dose is reduced by 50%.
For abortion (in combination with mifepristone): 36–48 hours after taking mifepristone, 400 mg of misoprostol is prescribed.
Overdose
The following possible consequences of an overdose were identified:
- Drowsiness, lethargy.
- Tremor.
- Cramps.
- Dyspnea.
- Abdominal pain.
- Diarrhea.
- Fever.
- Palpitations.
- Pressure reduction.
Interaction with other drugs
Eating antacids is accompanied by a decrease in the concentration of misoprostolic acid in plasma (clinically insignificant). When combined with magnesium-containing antacids, it is possible to increase diarrhea caused by misoprostol.
Long-term use of rifampicin, isoniazid, anticonvulsants, antidepressants, cimetidine, acetylsalicylic acid, indomethacin and drugs of the phenobarbital group, smoking more than 10 cigarettes a day stimulate the metabolism of misoprostol, reducing its level in the blood serum.
Within a week after taking misoprostol, you should stop taking acetylsalicylic acid and other NSAIDs.
Precautions for use
When used to terminate an early pregnancy, misoprostol should only be used in combination with mifepristone. These two drugs are indicated for use only as prescribed by a doctor and under his supervision in specialized medical institutions that check the quality of Mifepristone and Misoprostol. These institutions should have the means to provide emergency surgical gynecological and blood transfusion care appropriately trained medical personnel.
The use of the drug requires the prevention of Rhesus conflict and other general measures related to abortion. Before prescribing misoprostol, the patient should be informed in detail about the action and possible side effects of the drug.
The patient should be observed in a hospital setting for 4-6 hours before taking the drug. During and after taking the drug, the patient should be provided with timely medical care in case of massive bleeding or the development of other complications. After taking the drug in patients, as a rule, there is a slight vaginal bleeding, in some women it is very long.
With a very early pregnancy, abortion is possible after taking Mifepristone, but in this case, taking Misoprostol tablets is also necessary to optimize the results of medical abortion. After taking misoprostol in about 80% of women, abortion occurs within 6 hours and in about 10% of women within 1 week.
The patient must undergo a re-examination in the same medical institution 8-15 days after taking the drug. In case of incomplete abortion or ongoing pregnancy, estimated at 10-14 days after taking mifepristone, vacuum aspiration is mandatory, followed by histological examination of the aspirate.
Storage conditions
In a dry and dark place, at a temperature not exceeding 25 ° C.
Shelf life
24 months