Diltiazem
PrintQuick read
Calcium channel blockers can be used in pregnancy to treat angina and high blood pressure.
What are they?
Nine calcium channel blockers are used in the UK: amlodipine (Istin®), diltiazem (Tildiem®, Adizem®, Angitil®, Dilcardia®, Slozem®, Uard®, Viazem®, Zemtard®), felodipine (Cardioplen®, Delofine®, Felotens®, Folpik®, Neofel®, Parmid®, Vascalpha®), lacidipine (Motens®, Molap®), lercanidipine (Zanidip®), nicardipine (Cardene®), nifedipine (Adipine®, Nifedipress®, Tensipine®, Dexipress®, Valni®, Adalat®, Adanif®, Neozipine®, Nidef®, Fortipine®), nimodipine (Nimotop®), and verapamil (Half Securon®, Vera-Til®, Verapress®, Securon®).
Calcium channel blockers are mainly used to treat angina and high blood pressure.
Nifedipine is used to treat Reynaud’s phenomenon (a circulatory problem), verapamil can also be used to treat an arrhythmia (irregular heartbeat) and to prevent cluster headaches, and diltiazem cream might be prescribed to treat anal fissure.
Benefits
What are the benefits of using a calcium channel blocker in pregnancy?
Calcium channel blockers can prevent the pregnancy complications caused by high blood pressure and a related condition called pre-eclampsia. These complications include preterm birth, low infant birth weight, and illness in the mother and baby that can be serious.
Pregnant women with angina or an irregular heartbeat (arrhythmia) may need to continue using a calcium channel blocker to ensure that their heart remains healthy.
Use of a calcium channel blocker to treat Reynaud’s phenomenon, anal fissure, or to prevent cluster headaches can prevent the adverse effects on quality of life and wellbeing caused by these conditions.
Risks
What are the risks of using a calcium channel blocker in pregnancy?
There are no clear risks of taking a calcium channel blocker in pregnancy.
Nifedipine is commonly used in pregnancy and is unlikely to cause harm.
The other calcium channel blockers are less commonly used, and while not thought to cause problems, will only be recommended if the benefits of treating a potentially serious or lifestyle-impacting condition outweigh any possible risks.
Alternatives
Are there any alternatives to taking a calcium channel blocker in pregnancy?
Possibly. Other medicines can be used to treat high blood pressure or a heart problem in pregnancy but are not suitable for everyone. It is very important that these conditions are well-controlled, so staying on a calcium channel blocker might be the best option.
Women taking a calcium channel blocker for less serious conditions may be able to stop their medication during pregnancy.
Women who are taking a calcium channel blocker and planning a pregnancy, should speak to their doctor or specialist to make sure that it is ok to continue. No changes to medication should be made unless recommended by a doctor.
No treatment
What if I prefer not to take medicines in pregnancy?
It is important to take any medicines prescribed for high blood pressure or heart problems as these conditions can be serious for both mother and baby. Untreated high blood pressure can cause preterm birth, low infant birth weight, and illness in the mother and baby that can be serious. Additionally, it is vital for the woman’s wellbeing that any condition that greatly impacts quality of life remains as well-controlled as possible. A doctor will only prescribe medicines when necessary and will be happy to discuss any concerns.
Will I or my baby need extra monitoring?
As part of routine antenatal care, most women will be offered a very detailed scan at around 20 weeks of pregnancy to check the baby’s development. No extra monitoring for major birth defects is required following use of a calcium channel blocker.
In general, women with high blood pressure and/or heart problems will be more closely monitored during pregnancy to make sure that they remain well throughout and that their baby is growing as expected.
Are there any risks to my baby if the father has taken a calcium channel blocker?
There is no evidence that a calcium channel blocker used by the father can harm the baby through effects on the sperm.
Who can I talk to if I have questions?
If you have any questions about the information in this leaflet, please discuss them with your health care provider. They can access more detailed medical and scientific information from www.uktis.org.