Hello,
Thanks for the query,

Cold sore occur due to various reasons like stress , hormonal changes , minor injury , infection and allergens . Usually they go away by there own in few days without any treatment.

Apply ice pack to lips .

Take paracetamol for pain and swelling.

Take benadryl (anti allergic).

Apply ointment mupirocine on lip .

Consult dermatologist for proper diagnosis and rule out causes like herpes or pyogenic granuloma . Doctor may order blood test or swab test .

Doctor prescribe antibiotic ointment , steroid ointment anti viral drug or antibiotics depending upon diagnosis .

Wishing you a good health.
Thank you
Dr Harry Maheshwari

Hi..
Can understand your concern..

As per your query if you have history of recurrences of herpes infection causing cold sores there are high chances that your partner may get the infection as Herpes is sexually transmitted and the infection is transmitted from one infected partner to other..

In case if you do not have active sores present but the virus can be present over the surface of skin in a dormant stage or is lesser in number to represent the infection but the virus can be transferred to your partner and as the number of virus increase or the immunity of the body gets low there can be an outbreak of infection..

I would suggest you to get his investigations done like viral culture, Antigen-antibody reaction and Polymerase chain reaction to rule out the presence of virus in his body and can be given antiviral medications like Acyclovir as it helps in preventing outbreak of the disease..

Hope this information helps..

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Thanks and regards..
Dr.Honey Nandwani Arora..