Mood changes on Plan B: what to expect
Mood changes — anxiety, low mood, irritability, emotional blunting — are an under-recognised but important side-effect category for many medications. Whether Plan B (Levonorgestrel) at 1.5mg causes mood changes depends on Levonorgestrel and the indication. This page focuses on the practical pattern, what is normal and what calls for review.
Documented mood effects of Plan B
For some medications in Hormones and Birth Control, mood changes are part of the central indication. For others, mood changes are listed in the prescribing information for Levonorgestrel as side effects in a small subset of users, sometimes appearing in the first weeks of therapy and resolving spontaneously. Plan B's primary mechanism is delaying or preventing ovulation when taken before the LH surge.
When mood changes need review
Mild irritability or transient low mood in the first weeks on Plan B at 1.5mg is common and often improves. Persistent low mood, new anxiety that interferes with daily life, suicidal thoughts, or any sudden severe mood change warrants prompt review with the prescriber. According to current guidelines, suicidal ideation while starting any new medication should be treated as urgent.
Frequently asked questions
Can Plan B cause anxiety or depression? ▾
In some users yes — the prescribing information for Levonorgestrel lists mood-related effects as possible side effects in a subset of users. The frequency varies by medication; the prescriber can review whether Plan B or another factor is the most likely contributor at 1.5mg.
How long do mood side effects from Plan B last? ▾
Most mood side effects either resolve in the first weeks of Plan B as the body adjusts, or persist and call for clinical review. Persistent severe mood changes are not something to wait out alone; the prescriber should hear about them.
More on Plan B
- With alcoholPlan B and alcohol — is it safe to drink?
- With foodShould Plan B be taken with food?
- Side effectsPlan B side effects: common, rare and warning signs
- Dosage guidePlan B dosage guide: how much to take and when
- OnsetHow fast does Plan B start working?
- DurationHow long does Plan B last?
The information on this website is provided for reference and educational purposes only. It does not replace consultation with a qualified healthcare professional.