Drugs in Pregnancy Flashcards
What does a teratogen cause?
•abnormality within the baby following fetal exposure during pregnancy
When is the most vunerable part of pregnancy for teratogens?
First half of pregnancy is the most vulnerable- affect embryogenesis
What are some preventable teratogens?
- Alcohol- fetal alcohol syndrome
- Smoking- low birth weight, preterm birth, cerebral palsy, learning difficulties
- Marijuana, ecstacy, cocaine- low birth weight, withdrawl symptoms, learning and behavioural problems
What are pharmacokinetics?
- What the body does to a drug
- Movement of the drug through, and out of the body
- the time course - absorption, bioavailability, distribution, metabolism, and excretion.
What are pharmacodynamics?
- What the drug does to the body
- Biochemical /physiologic/ molecular effects of drugs on body
- Receptor binding/post receptor effect
Normal physiologic changes in pregnancy lead to what?
Alteration in the pharmacokinetics of the drug and may affect the pharmacodynamics
What did thalidomide cause?
Phocomelia
What drugs can be used to treat nausea and vomiting during pregnancy?
- Cyclizine- antihistamine
- Prochloroperazine- phenothiazine
- doxylamine/pyridoxine combination product (Xonvea®) was licensed for the treatment of NVP in the UK in 2018 and can also be offered as a first-line option.
- Second line- ondansetron, metoclopramide
What drugs can be used to treat hypertension during pregnancy?
•Labetolol, nifedipine, methyldopa, hydralazine
What are teratogenic hypertension medications?
ACE inhibitors, angiotensin receptor antagonist – change as soon as pregnancy confirmed
What are some safe epilepsy drugs during pregnancy?
Carbamazepine and lamotrigine-
What are some epilepsy medication teratogens during pregnancy?
- Phenobarbitone- cardiac malformations
- Sodium valproate- NTD, facial clefts
What should always be given in an epileptic pregnancy?
High dose folic acid
What are the NICE guidelines for diabetes during pregnancy?
All oral antidiabetic drugs, except metformin hydrochloride, should be discontinued before pregnancy (or as soon as an unplanned pregnancy is identified) and substituted with insulin therapy.
Women with diabetes may be treated with metformin hydrochloride [unlicensed in type 1 diabetes] as an adjunct or alternative to insulin in the preconception period and during pregnancy, when the likely benefits from improved blood-glucose control outweigh the potential for harm.
Metformin hydrochloride can be continued, or glibenclamide resumed, immediately after birth and during breast-feeding for those with pre-existing Type 2 diabetes.
All other antidiabetic drugs should be avoided while breast-feeding.
What is safe treatment for thromboembolism during pregnancy?
Low molecular weight heparin (LMWH)
What does warfarin do during pregnancy?
•fetal warfarin syndrome/fetal embryopathy
What is important with pregnancy and asthma?
•Risk of medication use are lower than risk of untreated asthama
What is safe to use to treat asthma during pregnancy?
B2 agonist- albuterol, salbutamol
What are some teratogenic treatments for asthma?
Theophyline- potential toxicity
•Systemic corticosteroid- severe asthama
What is a medication for headaches that can have teratogenic effects?
•Ibuprofen- persistent pulm hypertension- avoid in 3rd trimes
What is the effect of morphine based medicine during pregnancy?
- No increase in congenital abnormalities
- Risk of neonatal respiratory depression and with drawl
- Used as labour analgesia
When should you avoid codenine?
During lactation- infant opiate toxicity
What is important about SSRIs in pregnancy?
•Where the benefits of SSRI use outweigh potential risks, use of SSRIs during pregnancy may be indicated. The risks of destabilisation and maternal relapse must be taken into account when considering discontinuing SSRIs
What teratogenic effects can lithium cause?
•ebstein’s anomaly- cardiac anomaly
What are the teratogenic effects of diazepam?
Old studies clefts lip/palate- floppy infant syndrome
What are the teratogenic effects of quetiapine?
Large baby, poor neonatal adaptation syndrome
What is important about penicllin during pregnacy?
Generally safe- check allergy
What is important about macrolide during pregnacy?
•azithromycin/erythromycin- use only if no alternative
What is important about tetracycline during pregnacy?
•do not prescribe, animal studies- effects on skeletal development, discolouration of teeth
What is important about sulphonamides during pregnacy?
•teratogenic-avoid in first trimester- folate antagonist
What is important about aminoglycosides during pregnacy?
•auditory or vestibular nerve damage -The risk is greatest with streptomycin.
What is important about cephalosporins during pregnacy?
generally safe
What is important for cancer treatments during pregnancy?
- Most cytotoxic drugs are teratogenic
- Exclude pregnancy before starting these medications
- Take specialist advice- if needed to start or continue treatmet in pregnancy
What is the effect of hydroxychloroquine during pregnancy?
•no significant increased risk of major malformations in general, as well as craniofacial, cardiovascular, nervous system and genitourinary malformations specifically, and no significant increase in stillbirth, low birth weight or prematurity risks.
What is the effect of azithromycin during pregnancy?
•Although individual studies have described increased risks of miscarriage and overall malformation following azithromycin use in pregnancy, the majority of studies do not support these findings.
What is the effect of toclilizumab during pregnancy?
•Although adverse pregnancy outcomes have been described (including cases of congenital anomaly, miscarriages and preterm deliveries), the crude rates of these events do not generally appear to be notably increased above the background rate.
What is the effect of lopinavir during pregnancy?
•Approximately 3,000 exposed pregnancies and do not suggest an increased risk of malformation.[10] Studies investigating neurodevelopmental outcomes have also provided reassuring findings.[10] However, cases of preterm delivery, low birth weight and stillbirth have also been described.[24] Due to data limitations, the risk of these outcomes following maternal lopinavir/ritonavir use in pregnancy is currently undetermined.
What is the effect of corticosteroids during pregnancy?
majority of the best quality evidence does not suggest increased risks in either the overall malformation rate, or for specific malformations (including orofacial clefts and cardiac anomalies). The small number of methodologically limited studies investigating miscarriage and intrauterine death risks do not provide reliable evidence of increased risks, and similarly there is no reliable evidence indicating use of systemic corticosteroids impairs fetal growth
