Brief Answer:
Has significant interactions.

Detailed Answer:
I read your question and I understand your concern as Warfarin has many interactions with other drugs.

Unfortunately that applies to Primidone as well. Primidone does interact significantly with Warfarin by decreasing its levels in the blood, thus lowering its efficacy.

For that reason its use is not recommended, especially if you have only mild tremor not affecting your quality of life significantly.

If tremor increases and Primidone use becomes really necessary then an alternative to Warfarin might be considered. In recent years there have been some new oral anticoagulants approved for use in patients with nonvalvular Afib which have the benefit of not needing INR checking and having little interactions with other drugs. So their use can be considered eventually.

I remain at your disposal for other questions.

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