Brief Answer:
No dietary interactions

Detailed Answer:
I read your question carefully and I understand your concern regarding interactions.

In terms of diet restrictions thankfully no, neither gabapentin nor trazodone interact with any particular food, no worry about that.

They shouldn't be used with alcohol as they are all substances which act on the central nervous system and used together can have increased rate of side effects.

As for interactions with other drugs, Gabapentin doesn't have many significant interactions. It shouldn't be taken with substances which decrease its absorption like aluminium hydroxide, calcium carbonate, sodium bicarbonate or citrate, orlistat. Care is also needed with any drugs acting on central nervous system. That includes trazodone, while they do not interact by affecting each others levels, there is the more potential of side effects like drowsiness or dizziness (not necessarily but can happen).

Trazodone has some more significant interactions, with indapamide (a diuretic), several drugs used for arrhythmia (procainamide, quinidine, sotalol, amiodarone etc), clarithromycin and erythromycin (macrolide antibiotics), antifungals such as itraconazole and ketoconazole, antidepressants. The list for trazodone is long really can't be all mentioned, should be checked for any new drug added to your therapy.

I remain at your disposal for other questions.

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