Infants who are colicky do just as well as their non colicky peers with respect to temperament at one year of age.

Very few risk factors for choanal atresia have been identified. While causes are unknown, both genetic and environmental triggers are suspected. One study suggests that chemicals that act as endocrine disrupters may put an unborn infant at risk. A 2012 epidemiological study looked at atrazine, a commonly used herbicide in the U.S., and found that women who lived in counties in Texas with the highest levels of this chemical being used to treat agricultural crops were 80 times more likely to give birth to infants with choanal atresia or stenosis compared to women who lived in the counties with the lowest levels. Another epidemiological report in 2010 found even higher associations between increased incidents of choanal atresia and exposure to second-hand-smoke, coffee consumption, high maternal zinc and B-12 intake and exposure to anti-infective urinary tract medications.

Causes can be remembered by mnemonic HERNIA:

- Hereditary factors: the disease runs in families

- Endocrine imbalance: the disease tends to start at puberty and mostly involves females

- Racial factors: whites are more susceptible than natives of equatorial Africa

- Nutritional deficiency: vitamins A or D, or iron

- Infection: "Klebsiella ozaenae", diphtheroids, "Proteus vulgaris", "E. coli", etc.

- Autoimmune factors: viral infection or some other unidentified insult may trigger antigenicity of the nasal mucosa.

Specific infections, such as syphilis, lupus, leprosy and rhinoscleroma, may cause destruction of the nasal structures leading to atrophic changes. Atrophic rhinitis can also result from long-standing purulent sinusitis or radiotherapy of the nose, or as a complication of surgery of the turbinates. The United Kingdom National Health Service has stated that "Most cases of atrophic rhinitis in the UK occur when the turbinates are damaged or removed during surgery". Some authors refer to as Atrophic rhinitis secondary to sinus surgery as the empty nose syndrome.

Empty nose syndrome has been observed to affect a small proportion of people who have undergone surgery to the nose or sinuses, particularly those who have undergone turbinectomy (a procedure that removes some of the bones in the nasal passage). The incidence of ENS is variable and has not yet been quantified, but it is considered rare.

Untreated, the condition can cause significant and longterm physical and emotional distress in some people; some of the initial presentations on the condition described people who committed suicide. It is difficult to determine what treatments are safe and effective, and to what extent, in part because the diagnosis itself is unclear.

Nonallergic rhinitis is inflammation of the inner part of the nose that is not caused by an allergy. Nonallergic rhinitis involves symptoms including chronic sneezing or having a congested, drippy nose without an identified allergic reaction. Other common terms for nonallergic rhinitis are vasomotor rhinitis and perennial rhinitis. The prevalence of nonallergic rhinitis in otolaryngology is 40%. Allergic rhinitis is more common than nonallergic rhinitis; however, both conditions have similar presentation, manifestation and treatment. Nasal itching and paroxysmal sneezing are usually associated with nonallergic rhinitis in comparison to allergic rhinitis.

Nasal mucosa has rich blood supply and has venous sinusoids or "lakes" surrounded by smooth muscle fibers. These smooth muscle fibers act as sphincters and control the filling and emptying of sinusoids. Sympathetic stimulation causes vasoconstriction and shrinkage of mucosa, which leads to decongestion of nose. Parasympathetic stimulation causes not only excessive secretion from the nasal gland but also vasodilatation and engorgement, which lead to rhinorrhoea and congestion of nose. The autonomic nervous system, which supplies the nasal mucosa, is under the control of the hypothalamus. Therefore, emotions play significant role in nonallergic rhinitis.

The mortality rate of meconium-stained infants is considerably higher than that of non-stained infants; meconium aspiration used to account for a significant proportion of neonatal deaths. Residual lung problems are rare but include symptomatic cough, wheezing, and persistent hyperinflation for up to five to ten years. The ultimate prognosis depends on the extent of CNS injury from asphyxia and the presence of associated problems such as pulmonary hypertension. Fifty percent of newborns affected by meconium aspiration would die fifteen years ago; however, today the percent has dropped to about twenty.

Colic affects 10–40% of children. occurring at the same rate in boys and in girls.

Fetal distress during labor causes intestinal contractions, as well as relaxation of the anal sphincter, which allows meconium to pass into the amniotic fluid and contaminate the amniotic fluid. Meconium passage into the amniotic fluid occurs in about 5–20 percent of all births and is more common in overdue births. Of the cases where meconium is found in the amniotic fluid, meconium aspiration syndrome develops less than 5 percent of the time. Amniotic fluid is normally clear, but becomes greenish if it is tinted with meconium.

Maternal risk factors can include: preeclampsia, maternal hypertension, oligohydramnios, maternal infections, maternal drug use, placental insufficiency, and/or intrauterine growth restriction.

The risk of MAS increases after the 40th week of pregnancy.

In the case of infectious rhinitis, vaccination against influenza viruses, adenoviruses, measles, rubella, "Streptococcus pneumoniae", "Haemophilus influenzae", diphtheria, "Bacillus anthracis", and "Bordetella pertussis" may help prevent it.

Rhinitis medicamentosa is a form of drug-induced nonallergic rhinitis which is associated with nasal congestion brought on by the use of certain oral medications (primarily sympathomimetic amine and 2-imidazoline derivatives) and topical decongestants (e.g., oxymetazoline, phenylephrine, xylometazoline, and naphazoline nasal sprays) that constrict the blood vessels in the lining of the nose.

Choanal atresia is a congenital disorder where the back of the nasal passage (choana) is blocked, usually by abnormal bony or soft tissue (membranous) due to failed recanalization of the nasal fossae during fetal development.

The flow of blood normally stops when the blood clots, which may be encouraged by direct pressure applied by pinching the soft fleshy part of the nose. This applies pressure to Little's area (Kiesselbach's area), the source of the majority of nose bleeds, and promotes clotting. Pressure should be firm and be applied for at least five minutes and up to 20 minutes; tilting the head forward helps decrease the chance of nausea and airway obstruction. Swallowing excess blood can irritate the stomach and cause vomiting.

The causes of nosebleeds can generally be divided into two categories, local and general factors, although a significant number of nosebleeds occur with no obvious cause.

Initial treatment is similar to atrophic rhinitis, namely keeping the nasal mucosa moist with saline or oil-based lubricants and treating pain and infection as they arise; adding menthol to lubricants may be helpful in ENS, as may be use of a cool mist humidifer at home. For people with anxiety, depression, or who are obsessed with the feeling that they can't breathe, psychiatric or psychological care may be helpful.

In some people, surgery to restore missing or reduced turbinates may be beneficial.

A 2015 meta-analysis identified 128 people treated with surgery from eight studies that were useful to pool, with an age range of 18 to 64, most of whom had been suffering ENS symptoms for many years. The most common surgical approach was creating a pocket under the mucosa and implanting material - the amount and location were based on the judgement of the surgeon. In about half the cases a filler such as noncellular dermis, a medical-grade porous high-density polyethylene, or silastic was used and in about 40% cartilage taken from the person or from a cow was used. In a few cases hyaluronic acid was injected and in a few others tricalcium phosphate was used. There were no complications caused by the surgery, although one person was over-corrected and developed chronic rhinosinusitis and two people were under-corrected. The hyaluronic acid was completely resorbed in the three people who received it at the one year follow up, and in six people some of the implant came out, but this did not affect the result as enough remained. About 21% of the people had no or marginal improvement but the rest reported significant relief of their symptoms. Since none of the studies used placebo or blinding there may be a strong placebo effect or bias in reporting.

Environmental influences may also cause, or interact with genetics to produce, orofacial clefting. An example of how environmental factors might be linked to genetics comes from research on mutations in the gene "PHF8" that cause cleft lip/palate (see above). It was found that PHF8 encodes for a histone lysine demethylase, and is involved in epigenetic regulation. The catalytic activity of PHF8 depends on molecular oxygen, a fact considered important with respect to reports on increased incidence of cleft lip/palate in mice that have been exposed to hypoxia early during pregnancy. In humans, fetal cleft lip and other congenital abnormalities have also been linked to maternal hypoxia, as caused by e.g. maternal smoking, maternal alcohol abuse or some forms of maternal hypertension treatment. Other environmental factors that have been studied include: seasonal causes (such as pesticide exposure); maternal diet and vitamin intake; retinoids — which are members of the vitamin A family; anticonvulsant drugs; nitrate compounds; organic solvents; parental exposure to lead; alcohol; cigarette use; and a number of other psychoactive drugs (e.g. cocaine, crack cocaine, heroin).

Current research continues to investigate the extent to which folic acid can reduce the incidence of clefting.

Alcoholism is mistakenly attributed as a cause of this issue. Alcohol however may cause increased flushing in those affected.

If the condition thickens, turns red and irritated, starts spreading, appears on other body parts, or if the baby develops thrush (fungal mouth infection), fungal ear infection (an ear infection that does not respond to antibiotics) or a persistent diaper rash, medical intervention is recommended.

Severe cases of cradle cap, especially with cracked or bleeding skin, can provide a place for bacteria to grow. If the cradle cap is caused by a fungal infection which has worsened significantly over days or weeks to allow bacterial growth (impetigo, most commonly), a combination treatment of antibiotics and antifungals may be necessary. Since it is difficult for a layperson to distinguish the difference between sebaceous gland cradle cap, fungal cradle cap, or either of these combined with a bacterial infection, medical advice should be sought if the condition appears to worsen.

Cradle cap is occasionally linked to immune disorders. If the baby is not thriving and has other problems (e.g. diarrhea), a doctor should be consulted.

The most common complications of the posterior pharyngeal wall flap are hyponasality, nasal obstruction, snoring, and sleep apnea. Rarer complications include flap separation, sinusitis, postoperative bleeding, and aspiration pneumonia. Possible complications of the sphincter pharyngoplasty are snoring, nasal obstruction, difficulty blowing the nose.

Some researches suggest that sphincter pharyngoplasty introduces less hyponasality and obstructive sleep symptoms than the posterior pharyngeal wall flap. Both surgeries have a favourable effect on the function of the Eustachian tube.

Assurances that this condition will clear as the baby matures are very common. However, studies have shown that the condition occasionally persists into the toddler years, and less commonly into later childhood. It tends to recur in adolescence and persists into adulthood. In an Australian study, about 15 percent of previously diagnosed children still had eczema 10 years later. Sometimes, cradle cap turns into atopic dermatitis. Rarely, it turns out to be misdiagnosed psoriasis.

Allergic rhinitis is the type of allergy that affects the greatest number of people. In Western countries, between 10 and 30 percent of people are affected in a given year. It is most common between the ages of twenty and forty.

In a survey in New York city 35% of nursing mothers stopped breastfeeding after one week due to the pain of cracked nipples. Thirty percent stopped breastfeeding between weeks one and three. Another survey of breastfeeding mothers in Brazil reported that there was 25% higher risk of interruption of exclusive breastfeeding when the women had cracked nipples. Mothers with higher education levels are more likely to continue breastfeeding despite the pain of cracked nipples.

It can usually be corrected with augmentation rhinoplasty by filling the dorsum of nose with cartilage, bone or synthetic implant. If the depression is only cartilaginous, cartilage is taken from the nasal septum or auricle and laid in single or multiple layers. If deformity involves both cartilage and bone, cancellous bone from iliac crest is the best replacement. Autografts are preferred over allografts. Saddle deformity can also be corrected by synthetic implants of teflon or silicon, but they are likely to be extruded.

One way to prevent allergic rhinitis is to wear a respirator or mask when near potential allergens.

Growing up on a farm and having multiple brothers and or sisters decreases the risk.