The effects of TWYNSTA during pregnancy and lactation are not known. Effects related to the mono components are described as follows.
Pregnancy: Telmisartan: The use of angiotensin II receptor antagonists is not recommended during the first trimester of pregnancy and should not be initiated during pregnancy. When pregnancy is diagnosed, treatment with angiotensin II receptor antagonists should be stopped immediately, and, if appropriate, alternative therapy should be started.
The use of angiotensin II receptor antagonists is contraindicated during the second and third trimester of pregnancy. Preclinical studies with telmisartan do not indicate teratogenic effect, but have shown fetotoxicity.
Angiotensin II receptor antagonists exposure during the second and third trimesters is known to induce human fetotoxicity (decreased renal function, oligohydramnios, skull ossification retardation) and neonatal toxicity (renal failure, hypotension, hyperkalaemia).
Unless continued angiotensin II receptor antagonist therapy is considered essential, patients planning pregnancy should be changed to alternative anti-hypertensive treatments which have an established safety profile for use in pregnancy.
Should exposure to angiotensin II receptor antagonists have occurred from the second trimester of pregnancy, ultrasound check of renal function and skull is recommended.
Infants whose mothers have taken angiotensin II receptor antagonists should be closely observed for hypotension.
Amlodipine: The safety of amlodipine in human pregnancy has not been established. In animal studies, reproductive toxicity was observed at high doses.
Lactation: Twynsta is contraindicated during lactation since it is not known whether telmisartan is excreted in human milk. Animal studies have shown excretion of telmisartan in breast milk. Amlodipine is excreted in human milk. The proportion of the maternal dose received by the infant has been estimated with an interquartile range of 3-7%, with a maximum of 15%. The effect of amlodipine on infants is unknown. Because of the potential adverse reactions in nursing infants, a decision should be made whether to discontinue nursing or to discontinue therapy, taking into account the importance of this therapy for the mother (see Contraindications).
Fertility: No data from controlled clinical studies with the fixed dose combination or with the individual components are available.
Separate reproductive toxicity studies with the combination of telmisartan and amlodipine have not been conducted.
In preclinical studies, no effects of telmisartan on male and female fertility were observed.
In some patients treated by calcium channel blockers, reversible biochemical changes in the head of spermatozoa have been reported. Clinical data are insufficient regarding the potential effect of amlodipine on fertility. In one rat study, adverse effects were found on male fertility.