During pregnancy and while breastfeeding, every medication means a decision made for two people. The good news is that many common conditions can be treated safely; the important news is that no substance is guaranteed to be “risk-free”, and the golden rule stays the same: do not start, stop or change a treatment without asking your doctor or pharmacist. This guide explains the principles these decisions rest on, what is considered relatively safe, what to avoid and how to read medical information correctly.
The basic principle: the benefit/risk ratio
No medication is 100% safe in pregnancy. In practice, the doctor does not look for the “risk-free medication” but weighs the benefit/risk ratio: how great the benefit is for the mother (and, indirectly, for the foetus) against the potential risk of the exposure. Often, the risk of not treating an illness (uncontrolled high fever, a bacterial infection, decompensated asthma, epilepsy, hypothyroidism) is greater than the risk of a properly chosen treatment.
That is why “taking nothing” is not automatically the safe choice. Abruptly stopping certain chronic treatments (antiepileptics, levothyroxine, insulin, antidepressants) can be dangerous both for the mother and for the pregnancy. The decision is made on an individual basis, ideally before conception, when chronic treatments can be optimised in good time.
Three things matter almost every time:
- The trimester. The first trimester (organogenesis) is the period with the greatest teratogenic risk, but the third trimester also has its own sensitivities (see NSAIDs below).
- The dose and the duration. An occasional dose differs from chronic, high-dose treatment.
- The existence of alternatives with a better-documented safety profile.
Folic acid: the prevention that starts before pregnancy
Folic acid (vitamin B9) is one of the few “medication interventions” actively recommended around pregnancy. The World Health Organization (WHO) and European guidelines recommend folic acid supplementation to reduce the risk of neural tube defects (spina bifida, anencephaly).
- Usual dose: 400 micrograms (0.4 mg) per day, ideally started at least one month before conception and continued through the first trimester.
- Higher doses (usually 4–5 mg/day) may be recommended by the doctor in higher-risk situations (history of a pregnancy with a neural tube defect, diabetes, antiepileptic treatment, obesity). This decision belongs exclusively to the doctor.
On the Romanian market, folic acid is available both as a single product and in combined prenatal formulas. You can read separately about the role of vitamins in general in our guide on vitamins D, B and C.
What is considered relatively safe for pain and fever
For pain and fever, the “first-line” choice in pregnancy is generally paracetamol, at the lowest effective dose and for the shortest necessary duration. You will find details on dosing and precautions in the dedicated guide on paracetamol.
By contrast, non-steroidal anti-inflammatory drugs (NSAIDs) — ibuprofen, diclofenac, naproxen, ketoprofen — require special caution. The European Medicines Agency (EMA) has highlighted the risks of using NSAIDs in the second half of pregnancy (from around week 20), including reduced amniotic fluid and harm to the foetus’s kidneys; in the third trimester, NSAIDs are contraindicated because of the risk of premature closure of an important blood vessel in the foetus (the ductus arteriosus). More about this class in our guide on NSAIDs / non-steroidal anti-inflammatory drugs.
| Situation | Frequently considered option | Note (the decision belongs to the doctor) |
|---|---|---|
| Pain / fever | Paracetamol | Lowest effective dose, short duration; preferred over NSAIDs |
| NSAIDs (ibuprofen, diclofenac, naproxen) | To be avoided in the 3rd trimester; caution after week 20 | EMA warning; contraindicated close to term |
| Allergies / rhinitis | Second-generation antihistamines (e.g. loratadine, cetirizine) | Frequently used; only on recommendation — see antihistamines |
| Bacterial infections | Certain antibiotics (e.g. penicillins, cephalosporins) | Only when prescribed; tetracyclines and, as a rule, fluoroquinolones are avoided |
| Heartburn / reflux | Dietary measures; certain antacids | Ask the pharmacist what is suitable in pregnancy |
Note: the table is indicative and educational, not a treatment recommendation. Specific brand names and doses are established individually with the doctor or pharmacist.
Risk categories: the old FDA system (A/B/C/D/X) as an educational reference
Many people have heard of the “pregnancy categories” A, B, C, D, X. This was a system of the American FDA agency, useful as a historical benchmark, but which was replaced from 2015 by a new information format (Pregnancy and Lactation Labeling Rule, PLLR), precisely because the letters oversimplified clinical reality. We present them only as an educational reference:
| Category (old FDA) | Simplified meaning | Illustrative examples |
|---|---|---|
| A | Human studies have not shown risk | Folic acid at usual doses |
| B | No evidence of risk in humans | Many penicillins, paracetamol (usual use) |
| C | Risk cannot be excluded; the benefit may justify it | Numerous common medications |
| D | There is evidence of risk, but the benefit may prevail | Some antiepileptics |
| X | Contraindicated in pregnancy; the risk outweighs the benefit | Isotretinoin, thalidomide |
The practical takeaway: do not rely on a medication’s “letter” found on the internet. The system was abandoned precisely because it led to wrong decisions. The correct source is the official product information and professional advice.
Medications known to be risky (to be avoided without a clear indication)
There are substances recognised as teratogenic or carrying significant risk, which the doctor avoids or manages with special precautions in pregnancy:
- Isotretinoin (severe acne) — major malformation risk; requires strict contraception.
- Valproic acid and some antiepileptics — increased risk; treatment is adjusted in good time, never stopped abruptly without a doctor.
- Warfarin (anticoagulant) — risk during certain periods; see also the class of anticoagulants and antiplatelet agents.
- ACE inhibitors / sartans (certain antihypertensives) — to be avoided especially in the 2nd–3rd trimester.
- Tetracyclines (a type of antibiotic) — affect the development of bones and teeth.
- Methotrexate and other cytotoxics — contraindicated.
This list is not exhaustive and does not mean that, if you took something before knowing you were pregnant, all is lost — many accidental exposures carry low risk. The important thing is not to panic and to talk to your doctor quickly.
Breastfeeding: what passes into milk and what matters
Almost any medication passes, in varying amounts, into breast milk — but “passes” does not automatically mean “dangerous”. What matters is how much reaches the milk, how much the infant absorbs and how toxic the substance is for them. For many common medications, the amount that reaches the baby is very small.
Practical pointers for the breastfeeding period:
- Prefer medications with a well-documented profile and short-term administration.
- Ask about the timing of the dose relative to feeding — sometimes an interval can be chosen that reduces the infant’s exposure.
- For pain/fever, paracetamol is generally considered compatible with breastfeeding; many short-term NSAIDs are too — but confirm with the pharmacist.
- Be careful with substances that can reduce milk production or cause drowsiness in the infant.
- Premature infants or those with health problems require additional caution.
An international resource used by professionals for breastfeeding compatibility is the LactMed (NIH) database; for your specific decisions, however, always ask your doctor or pharmacist.
How to check correctly and what to ask the professional
Information on forums and social media is often contradictory. Trustworthy sources are the summary of product characteristics (SmPC) approved by ANMDMR (Romania’s National Agency for Medicines and Medical Devices), the communications of EMA, and the NICE and BNF guidelines. Learn to read the “Pregnancy and breastfeeding” section of the patient leaflet — we explain how in the guide on how to read the patient leaflet. Also remember the difference between over-the-counter and prescription medicines, detailed in OTC vs. Rx: the fact that a product is OTC does not automatically make it safe in pregnancy.
Useful questions for the doctor or pharmacist:
- Is this medication suitable for the trimester I am in / for the breastfeeding period?
- Is there an alternative with a better-known safety profile?
- What is the lowest effective dose and for how long?
- What warning signs (in me or the baby) should make me come back?
- Can I continue the chronic treatment I am already taking, or does it need adjusting?
In Romanian pharmacies — Catena, Dona, Help Net, Dr.Max, Farmacia Tei and independent pharmacies — you can always ask for the pharmacist’s advice before buying a “trivial” product during pregnancy or breastfeeding. It is free, quick and exactly the kind of check that matters when a decision concerns two people.
In short: no medication is perfectly safe, but many conditions are treated correctly in pregnancy and breastfeeding. Folic acid is started before conception, paracetamol often remains the first option for pain and fever, NSAIDs are avoided towards the end of pregnancy, and for anything else — the question put to the doctor or pharmacist is the safest “dose”.