Don’t just glance at the title and then ask, “Is he off his rocker?” “What’s in the water cooler at Atlanta Hyperbaric?” No, I said oxytocin, not OxyContin®. The first is a hormone, sold under the trade name of Pitocin®, and the second is an opioid pain killer with a habit-forming potential. It’s an easy mistake to make, unless you happen to be a pharmacist or are otherwise familiar with these drugs.
Oxytocin was first isolated in 1953 and has been available to physicians at least since I was a medical student in the 1960’s. Oxytocin is commonly used by obstetricians (as a “pit drip”) in the induction and management of labor and delivery. Of course, just because a drug is old and familiar, doesn’t make it good, bad, safe or dangerous. But, old drugs are relatively well studied and predictable, so it is always welcome news when researchers start looking at new indications for an old drug.
Oxytocin has profound and complex behavioral effects, largely documented in animals, but increasingly observed in people. In humans, oxytocin induces trust, increases generosity, but also stimulates envy and gloating. Oxytocin has even been called the love hormone. Autism is characterized by three symptom categories: speech and communication abnormalities, social functioning impairments and repetitive behaviors and restricted interests. Plasma oxytocin levels have been reported to be abnormally low in autistic patients, so it is not surprising that this powerful drug is also being tried as an autism treatment.
This week a group of French researchers reported that oxytocin improved the abilities of autistic adults to interact with other people. The researchers had the patients play a video ball-tossing game, in which the patients threw balls to cartoon characters with three different behavioral profiles: One player always returned the ball to the patient, another player never returned the ball, and the third player indiscriminately returned the ball to the patient or to other players. Before oxytocin, the patients threw the ball randomly to all three players, but after oxytocin, the patients preferred to throw to the guy who threw it back to them.
The scientists also measured the patients’ attentiveness to social signals. Patients looked at photos of faces on a computer and were asked to identify either the gender or whether the face was looking into the camera or away to one side. The focus of participants’ gaze was recorded. Mean time spent looking at the faces, as opposed to elsewhere, was about 20% to 30% greater following oxytocin treatment both in the gender identification and the facial-direction tasks. The patients also would sometimes look directly at the eyes in the photos, which they never did without oxytocin.
At baseline, mean plasma oxytocin levels were 1.08 pg/mL in patients compared with 7.28 pg/mL in the healthy controls (P<0.0001). Ten minutes after intranasal oxytocin in the patients, their plasma levels were still only 2.66 pg/mL, yet despite the persistent shortfall in plasma oxytocin and substantial individual variability in performance, the lead investigator said, “We demonstrated that oxytocin can promote social approach and social comprehension in patients with autism.”
This study is great stuff. Of course, it only looked at a few adult patients and researcher biases could have poisoned the well. But I am encouraged and time will tell whether oxytocin replacement therapy can help autistic patients, children and adults, over the long run.