Brief Answer:
Medications Penicillin and Guaifenesin can be taken together.

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

I have read through your query in detail.
To the best of my knowledge and after having reviewed latest medical literature Penicillin (an antibiotic medication prescribed in infections) and Guaifenesin (an expectorant given for cough) do not interact with each other when taken in prescribed doses and can be safely taken together.

However should in the rare possibility of you having any discomfort after taking the medications, please inform your doctor immediately.

Hope this answers your question. Please feel free to correct any oversight in my interpretation of your problems and discuss them in detail as per your requirements.

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

Regards,
Dr.Vivek

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