If you have just discovered you are pregnant and take medication for a mental health condition, the most important thing on this page is this: do not stop it on your own. Contact your prescriber promptly, ideally the same week.
The instinct to stop immediately is understandable and very common. It is also the response most likely to cause harm, for two reasons. Stopping abruptly can cause withdrawal effects and a high risk of relapse, often within weeks. And untreated mental illness in pregnancy is not a neutral option: it carries its own risks to both you and the pregnancy.
The real decision is never medicine versus no risk. It is a comparison between the risks of treatment and the risks of the untreated condition, and that is a judgement to make with a clinician who knows your history.
Common side effects and early adjustment effects
The everyday side effects of these medicines do not change because you are pregnant, though some may be harder to distinguish from pregnancy itself. Nausea, tiredness, sleep disruption and appetite change are common to both, which can make it difficult to judge what is causing what.
Dose requirements can also change during pregnancy as your body processes medicines differently, so a dose that was stable may need reviewing rather than assuming it still fits. See mental health medication side effects.
Serious mood, behaviour or physical symptoms to take seriously
Get urgent help for new or worsening thoughts of self-harm, thoughts of harming the baby, or a marked deterioration in mood. Risk around pregnancy and after birth is a recognised concern and is treatable, but only if raised.
Contact your team the same day if you have already stopped a medicine abruptly and feel unwell, or if symptoms of your condition are returning.
Some medicines require specific attention in pregnancy. Sodium valproate in particular carries serious risks of birth defects and developmental problems and is not used in pregnancy or in those who could become pregnant except under strict conditions. If you take it, contact your specialist urgently rather than stopping, since abrupt withdrawal can cause seizures. See sodium valproate side effects.
Lithium also needs specialist input and closer monitoring in pregnancy. See lithium side effects.
Sexual, sleep, weight and emotional side effects
Sleep disruption and mood variability are common in pregnancy regardless of medication, which makes it harder to tell whether treatment is still working. Keeping a simple record of how you are doing week to week gives your team something concrete at appointments, rather than relying on recall at a single visit.
Weight change in pregnancy is expected, so weight-related side effects need interpreting differently here.
Interactions, alcohol, pregnancy and other risk factors
Planning ahead is far better than reacting. If you take mental health medication and might become pregnant, raise it before conceiving. That allows time to review whether a different medicine would be preferable, to make any change gradually while you are well, and to arrange the right monitoring. Roughly half of pregnancies are unplanned, which is exactly why the conversation is worth having early rather than at the point it becomes urgent.
Other points to raise: folic acid, which is recommended before conception and in early pregnancy, and may be advised at a higher amount with some medicines; whether your medicine affects contraception or vice versa; and what happens after birth, including breastfeeding. See mental health medication and breastfeeding.
Tell anyone treating you during pregnancy what you take, including maternity staff, since some medicines affect care around delivery and in the days afterwards.
What to ask your doctor before changing dose or stopping
- What is known about this specific medicine in pregnancy?
- What are the risks of my condition being untreated, for me and the pregnancy?
- Is there an alternative better established in pregnancy, and is switching worth the disruption?
- Will my dose need adjusting as pregnancy progresses?
- Should I take folic acid, and at what amount?
- What is the plan for after the birth, including breastfeeding?
- Who do I contact if my mood worsens?
Related mental health medication guides
- Mental health medication side effects
- Should I stop my mental health medication
- When to call a doctor
- OTC medicines in pregnancy
- Report a side effect in South Africa
Medical Disclaimer: This content is for informational and educational purposes only and does not constitute medical diagnosis, prescription, or professional advice. Always read the patient information leaflet and consult a qualified doctor or pharmacist regarding any medicine or health concern.