The good news is that pre-existing migraine often gets better in pregnancy, especially migraine without aura and premenstrual migraine. However, it’s important to know a) how to treat it when it occurs and b) how to avoid confusing more dangerous causes of headache with migraine.
Treatment of pain
- Paracetamol should be used first-line
- Ibuprofen can be considered but has less safety data than paracetamol and should be avoided in the third trimester (risk of premature closure of the ductus arteriosus)
- Opiates are considered safe in pregnancy, but can exacerbate nausea/reduce gastric mobility, so the article advises avoiding them, although frankly I think that may be too strong a piece of advice given that you may well end up without other safe options for treating someone in pain.
Treatment of nausea
The choice is better here. Cyclizine is first-line, but other acceptable choices include prochlorperazine, domperidone, ondansetron and metoclopramide (although avoid long-term use of the latter due to its extrapyramidal SEs).
- Aspirin 75 mg od. Often helpful for migraine prevention in pregnancy (which makes me wonder whether it’s been tried as a prophylactic outside of pregnancy, since it would surely have a role there) and has been used safely up to 36 weeks gestation in a recent RCT.
- Beta-blockers, such as propranolol 10 – 40 mg tds or the equivalent dose once daily. Studies did not find use in the first trimester to be associated with an increase in rate of congenital anomalies.
- Low dose TCAs; e.g. amitriptyline 10 – 25 mg nocte.
- Sudden-onset headache reaching maximal intensity in <1 minute – could be a bleed
- New onset severe headache or significant change in headache type.
- Headaches progressively worsening over time
- Features of meningitis
- Features of RICP
- Orthostatic headache (changes with posture)
- New-onset focal neurological deficit
- Visual disturbance or visual field defect
- New-onset seizures or cognitive dysfunction
- Impaired consciousness
- Personality changes
- Head or neck trauma in the past 3 months (and, unlike most of the others, this is one I wouldn’t have known to be a problem)
- Unusual aura (e.g. >1 hr duration, associated motor weakness)
- Symptoms of GCA
- Symptoms of glaucoma
- Raised BP/symptoms of pre-eclampsia
- History of neurological conditions
- History of pituitary problems
- History of immunocompromise
- History of malignancy
- History of conditions associated with procoagulable state
- FH of ICH
And, less urgently:
- Medication that might contribute to the headache: e.g. CCBs.
- Possible medication overuse headache.