It could've been allergies

[Meclazine for Israel]

From forbes.com

Trump may have allergies: Allergies are the most common cause of chronic sniffling. This time of the year (August to November) ragweed is the most common culprit. Mold and fungi are other common possibilities in September and October.

Trump may have chronic sinusitis: Sinusitis is inflammation of the sinuses, which blocks mucus drainage, which, in turn, may impair breathing. Allergies can lead to chronic sinusitis. So can growths in the nose like nasal polyps as well nasal defects such as a deviated nasal septum. Viral, bacterial and fungal infections are also common causes. Heartburn, otherwise known as gastroesophageal reflux (if you haven’t watched all the pharmaceutical commercials about heartburn that may give you heartburn), can also cause chronic sinusitis. Add cystic fibrosis and immune system problems to the list too.

Trump may be irritated by something: This could explain the slightly constipated look. Common irritants include perfume or cologne, cigarette smoke and air pollution. Cold weather and bright lights can also cause irritation.

Trump may be taking medications that cause sniffling: Medications that have sniffling as a possible side effect include blood pressure, birth control, antidepressant, antipsychotic and erectile dysfunction medications. Delivering medications to the nose can also cause irritation of the nasal passages such as steroid nose sprays for allergies and shoving Viagra up your nose.

Trump may be pregnant: Less likely but if this is the cause, he is probably in his third trimester, and the sniffles should resolve within a few weeks of delivery.

Trump may have a tic: Note this is not the bug, which is spelled tick. Trump does not have ticks as far as I can tell. A tic is an involuntary muscle movement, meaning that it is not deliberate. This would probably not be a simple childhood tic because Trump is not a child, age-wise. Tics can occur when a person has attention deficit hyperactivity disorder (ADHD), myoclonus, obsessive-compulsive disorder, epilepsy or Tourette’s syndrome. Anxiety and stress can also lead to tics.

Trump may be crying: Debates can be tough. People who are very sensitive or strongly empathetic and sympathetic can also be prone to crying.

Trump may have repeated head trauma: Blows to the head via sports such as football, boxing, soccer and ice hockey, or hitting your head with a brick over beauty pageant winners gaining weight, can cause irritation and even leakage of brain fluid into the nasal passages.

Trump may have picked his nose too much or too aggressively: Nose picking can irritate the nasal passages and even lead to nosebleeds.

Trump may have bleeding problems: Anything which decreases the ability of blood to clot properly, such as use of aspirin or blood thinners, and bleeding disorders such as hemophilia, can lead to nosebleeds.

Trump may have something up his nose: Children often jam objects such as beans, peas and peanuts up their nose, which in turn can irritate the inside of their noses. Some adults do this as well.