Drug interactions
Estrogens conjugated synthetic + Lorlatinib
Severity: Moderate
Estrogens conjugated synthetic and Lorlatinib: moderate interaction.
Last updated
For healthcare professionals — reference only. This page is a brief summary, not medical advice and not a substitute for official labeling or clinical judgement. Always verify before prescribing or dispensing.
Summary
Lorlatinib induces CYP3A and may lower synthetic conjugated estrogen concentrations, reducing hormone therapy effect. Symptoms such as vasomotor complaints or breakthrough bleeding may result.
What this interaction means in plain words
Estrogens conjugated synthetic and Lorlatinib can affect each other. The combination is often manageable, but it may need a change of dose, a change of timing, or extra checks while both are taken.
Why it happens
Lorlatinib induces CYP3A4, accelerating estrogen metabolism.
What to do
Monitor for reduced estrogen effect and adjust dose as needed. Use non-hormonal contraception if contraception is intended.
What to ask your pharmacist
- Should I take them at different times of day?
- Does the dose of either medicine need to change?
- Is there anything I should avoid, such as alcohol or certain foods, while on both?
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Other interactions of Lorlatinib
- Amobarbital + Lorlatinib Contraindicated
- Apalutamide + Lorlatinib Contraindicated
- Butabarbital + Lorlatinib Contraindicated
- Carbamazepine + Lorlatinib Contraindicated
- Enzalutamide + Lorlatinib Contraindicated
- Fosphenytoin + Lorlatinib Contraindicated
Frequently asked questions
Can I take Estrogens conjugated synthetic with Lorlatinib?
MediHelp rates the interaction as moderate. Estrogens conjugated synthetic and Lorlatinib can affect each other. The combination is often manageable, but it may need a change of dose, a change of timing, or extra checks while both are taken. Lorlatinib induces CYP3A and may lower synthetic conjugated estrogen concentrations, reducing hormone therapy effect. Symptoms such as vasomotor complaints or breakthrough bleeding may result.
How serious is the interaction between Estrogens conjugated synthetic and Lorlatinib?
MediHelp rates it moderate, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Monitor for reduced estrogen effect and adjust dose as needed. Use non-hormonal contraception if contraception is intended.
What other medicines interact with Lorlatinib?
MediHelp also lists interactions of Lorlatinib with, for example, Amobarbital, Apalutamide, Butabarbital. The full list is on the Lorlatinib page.
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