As pleasurable as the activity is, sex can be a complex and rather sensitive issue for many couples. An array of factors can come together and lead up to either a good time in bed or awkward situations that you would both rather forget about.
Aside from the more common culprits (such as erectile dysfunction or stress), there is another less severe but rather annoying condition that you may or may not have even heard of: a stuffy blocked nose, occurring during or after sex.
A reader on DoctorxDentist asked about why the nose can become stuffy and blocked after sex. Psychiatrist, Dr Ng Beng Yeong, responded. Here’s what he had to say.
The condition is known as “Honeymoon Rhinitis” (no joke)
Honeymoon Rhinitis is best described as a condition that presents nasal congestion during sexual intercourse. This is due to the many blood vessels in the soft tissues of the nose (called turbinates) swelling up during sex.
This can lead to blocked nasal passages that create congestion.
Symptoms of the honeymoon rhinitis are similar to non-allergic rhinitis: 
- blocked nose
- runny nose (rhinorrhea)
- mild irritation or discomfort in the nose-area
- reduced sense of smell
How does this happen?
During sexual arousal, the sympathetic nervous system is triggered and the blood vessels constrict. This is generally why there is less blood flow to the nose and the nose eventually opens up.
This can lead to unpleasant rhinitis-like symptoms that generally go away slowly after orgasm. 
It can also cause sneezing
Sneezing isn't just a reflex that helps clear the nasal passages of irritants.
Studies have confirmed that sneezing can also be induced by sexual ideation or orgasm. Sexually induced sneezing occurs independently from external stimuli, so it isn't caused by any allergens in the air. 
It can occur at any point during sex
Honeymoon rhinitis has been known to occur at any point during a sexual experience. It isn't exclusively after sex or before. 
It's more common than you think
Turbinates in the nose contain erectile tissue. They dictate blood flow and can possibly lead to congestion. Honeymoon rhinitis is, in fact, a well-known phenomenon that can occur in both men and women.
It's more common than you might think because unusual or embarrassing symptoms during sex may not be easy to discuss with physicians. This is why many people may often decide against seeking advice. 
Honeymoon nose is genetic as well
Studies have indicated that honeymoon rhinitis may possibly be inherited through genetics. 
However, it can be difficult to know about this genetic association. This is because, in general, it’s unlikely that parents and children will discuss such private issues with each other.
Who discovered this phenomenon?
In the 19th century, suspicions were already pointing to honeymoon rhinitis, with Watson in 1875 and John Nolan Mackenzie in 1884 noting a link between sexual excitement and the nose.
However, no credible reason was given until 2008, when Dr Mahmood Bhutta and Dr Harold Maxwell conducted the first full-scale investigation on the matter. 
By the way, it's also caused by viagra
The drug Sildenafil (Viagra™) may also cause honeymoon rhinitis.
Patients have reported nasal stuffiness that subsides about four to six hours after using the drug.
One patient even reported having nasal stuffiness that was so severe he was unable to breathe through the nose. Do consult a doctor before being prescribed any drugs for sexual intercourse. 
Any ENT health questions you'd like to ask?
1. NHS Choices. Overview - Non-allergic rhinitis. Published 2019. Accessed July 4, 2019.
2. McCorry LK. Physiology of the autonomic nervous system. American journal of pharmaceutical education. 2007;71(4):78. doi:10.5688/aj710478
3. Bhutta MF, Maxwell H. Sneezing induced by sexual ideation or orgasm: an under-reported phenomenon. Journal of the Royal Society of Medicine. 2008;101(12):587-591. doi:10.1258/jrsm.2008.080262
4. Mackay IS. Rhinitis and sinusitis. British Journal of Diseases of the Chest. 1988;82:1-8. doi:10.1016/0007-0971(88)90002-2
5. Mazzatenta A, De luca C, Di tano A, Cacchio M, Di giulio C, Pokorski M. Swelling of Erectile Nasal Tissue Induced by Human Sexual Pheromone. Adv Exp Med Biol. 2016;885:25-30.
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7. Scadding GK, Durham SR, Mirakian R, et al. BSACI guidelines for the management of allergic and non-allergic rhinitis. Clinical & Experimental Allergy. 2007;38(1):19-42. doi:10.1111/j.1365-2222.2007.02888.x
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