Brief Answer:
You will likely be ok but please watch for side effects as mentioned below

Detailed Answer:
Hi XXXX XXXXXXX
Thanks for writing in to us.

I have read through your query in detail.
Please find my observations below.

1. Zoloft contains sertraline and is a selective serotonin reuptake inhibitor which works on the central nervous system.

2. Nyquil is a cold medicine and there are many preparations. The various Nyquil preparations might contain combinations acetaminophen / dextromethorphan / doxylamine / phenylephrine. Please write back with the exact name of the Nyquil preparation you are taking so that I can confirm the contents.

3. Probable interactions between Zoloft and Nyquil include the following
(i) Dextromethorphan in Nyquil and sertraline in Zoloft might rarely interact and cause a serious side effect. This usually applies to people who take these medicines regularly. It is less likely for you but if you develop symptoms like confusion, hallucination, seizure, extreme changes in blood pressure, increased heart rate, fever, excessive sweating, shivering or shaking, blurred vision, muscle spasm or stiffness, tremor, incoordination, stomach cramp, nausea, vomiting, and diarrhea then please consult your doctor immediately.

(ii) Sertraline in Zoloft and doxylamine in Nyquil can interact and cause increased drowsiness and difficulty in concentration. You should avoid driving and participating in activities requiring high alertness if you have taken Nyquil preparation containing doxylamine.

Hope your query is answered.
Please do write back if you have any doubts.

Regards,

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