Allylestrenol is an orally active gestagen. Allylestrenol has a pronounced pregnancy maintaining action in castrated animals without producing hormonal side-effects. In the human, premature termination of pregnancy often follows a fall in the levels of placental hormones. Allylestrenol has been shown to stimulate the placental progesterone production in vitro & to promote the secretion of placental hormones (human chorionic gonadotrophin, human placental lactogen, oestrogens and progesterone) and oxytocinase in patients with pregnancy at risk. In aggrement to this the trophoblastic layers of the placenta show histological signs of activation. Clinical studies have indicated that Allylestrenol is an effective & safe pregnancy preparation. Administration of Allylestrenol in combination with bed rest can remove or prevent the threat of abortion in early pregnancy or stop threatened premature labor.


Allylestrenol is used for -

  • - Intra uterine Growth Retardation (IUGR)
  • - Threatened abortion
  • - Habitual abortion
  • - Threatened premature labor
  • - Failure of nidation

Allylestrenol is also used to associated treatment for these conditions: Abortions spontaneous, Premature Labour


Trade Name Allylestrenol
Generic Allylestrenol
Allylestrenol Other Names Alilestrenol, Allilestrenolo, Allyl estrenol, Allylestrenol, Allylestrenolum, Allyloestrenol
Formula C21H32O
Weight Average: 300.4782
Monoisotopic: 300.245315646
Therapeutic Class Female Sex hormones
Available Country
Last Updated: August 5, 2021 at 12:40 pm


Allylestrenol Structure


Allylestrenol dosage

Allylestrenol should be taken orally. The dose of the drug depends on the indication.

Intra Uterine Growth Retardation [IUGR]: 1 tablet three times a day at least two months. Reduce the dose if symptoms improve.

Threatened Abortion: 1 tablet thrice daily for 5-7 days. The treatment period may be extended depending on necessity. After symptoms disappear, the dosage should be gradually reduced.

Habitual Abortion: 1 to 2 tablets daily with the confirmation of pregnancy. Administration should be continued until at least one month after the critical period.

Threatened Premature Labour: 40 mg daily until symptoms improve.

Failure of Nidation: 2 - 4 tablets daily from 16th to 26th day of the cycle until conception is achieved.

Side Effects

Gastrointestinal complaints like nausea, vomiting etc. have been reported.


Patients with the following conditions should be cautious: Heart disease, congestive heart failure, sick sinus syndrome, coronary artery disease, seizures, epilepsy, renal dysfunction, migraine headaches, or breathing diseases including asthma, emphysema, chronic bronchitis, or COPD, breast-feeding.

Pregnancy & Breastfeeding use

Allylestrenol is extremely safe. Serious adverse reactions have neither been reported in mother. It is free from anti-ovulatory and androgenic properties. Allylestrenol produces no masculinization of female foetus.


Hypersensitivity; thrombophlebitis; undiagnosed vaginal bleeding, incomplete abortion, hormone-dependent carcinoma, cerebral apoplexy, as a diagnostic test for pregnancy; severe hepatic impairment.

Special Warning

It should not be used for children younger than 16 years old.

Acute Overdose

If you have taken several capsules at once, there is no need for great concern. However, you should consult your doctor. The oily substance in the capsule may cause diarrhea.

Interaction with other Medicine

No drug- drug interactions have been reported.

Storage Condition

- Store in a cool, dry place

- Keep away from light & out of reach of children