Drug interactions
Carbidopa + Hydralazine
Severity: Moderate
Carbidopa and Hydralazine: 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
Carbidopa is given with levodopa, and the dopaminergic therapy can cause orthostatic hypotension. This can add to the blood pressure lowering effect of hydralazine. Carbidopa alone has little direct effect.
What this interaction means in plain words
Carbidopa and Hydralazine 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.
Carbidopa belongs to Central Nervous System; Hydralazine belongs to Cardiovascular.
Why it happens
Additive hypotensive effects arise from levodopa-derived dopamine, with carbidopa increasing levodopa availability.
What to do
Monitor standing and sitting blood pressure when starting or adjusting levodopa/carbidopa. Reduce the hydralazine dose if symptomatic hypotension develops.
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 Hydralazine
- Amifostine + Hydralazine Major
- Aceclofenac + Hydralazine Moderate
- Acemetacin + Hydralazine Moderate
- Aldesleukin + Hydralazine Moderate
- Avanafil + Hydralazine Moderate
- Benzphetamine + Hydralazine Moderate
Other interactions of Carbidopa
Frequently asked questions
Can I take Carbidopa with Hydralazine?
MediHelp rates the interaction as moderate. Carbidopa and Hydralazine 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. Carbidopa is given with levodopa, and the dopaminergic therapy can cause orthostatic hypotension. This can add to the blood pressure lowering effect of hydralazine. Carbidopa alone has little direct effect.
How serious is the interaction between Carbidopa and Hydralazine?
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 standing and sitting blood pressure when starting or adjusting levodopa/carbidopa. Reduce the hydralazine dose if symptomatic hypotension develops.
What other medicines interact with Hydralazine?
MediHelp also lists interactions of Hydralazine with, for example, Amifostine, Aceclofenac, Acemetacin. The full list is on the Hydralazine page.
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