Josh Trebach, MD

18 Nov 2024

I finally figured out a study technique that worked well for me and I wanted to share it with my bluesky friends! A thread on the technique that got me through med school, residency, fellowship, and the hardest board exam I’ve ever taken:🧵📚

A 5-year-old male presents to the emergency department with inability to move his arms/legs and difficulty breathing. Family reports they found him ingesting these fireworks (see image). What lab do you expect to be abnormal and why? ☠️☠️☠️☠️☠️

Treatment of sick patients with ingestion of barium salts like this includes: -potassium replacement (watch for rebound hyperkalemia) -cardiac/airway monitoring -possibly dialysis -consider giving an oral sulfate salt to bind up the barium -call your local poison center!!!

The (fictional) patient in the first tweet was based off real cases where people (or animals) have ingested these fireworks. For more cases check out the following cases: PMID: 42204929, 15675995, 24905573 Want more toxicology cases? Want to be a toxicologist? Let me know! 😊

When ingested, barium causes blockade of potassium efflux = potassium cannot exit cells. The Na/K pump continues to do its normal thing, pumping K in/pumping Na out of the cell. This leads to a profound hypokalemia. One case showed a K of 0.2 mEq/L!! (PMID: 23024089)

Hypokalemia can lead to dangerous complications including muscle weakness/paralysis (including respiratory muscle paralysis) and cardiac complications (QT interval prolongation, ventricular tachycardia, cardiac arrest). Image below is vtach from a barium case (PMID: 19876854)

This patient ingested fireworks (specifically "snake" fireworks) and these classically can contain BARIUM which can lead to devastating HYPOKALEMIA. But why is barium in fireworks? And how does it cause hypokalemia? Let’s talk toxicology…

Barium salts are usually put in fireworks to give them a cool green flame pattern when burned. However, in the "snake" fireworks, the barium is more of an oxidizer for the smoldering reaction that generates the large carbonaceous residue or "snake" (looks like poop to me tho)

22 Sept

don’t make fun of neurologists until you walk a myelin their shoes

6 Sept

sadly this is not the worst cpr i have seen

1 Sept

didn’t think I needed to say this but epipens do not contain beta blockers and this home brew “allergy kit” is not a substitute for an actual epipen

24 Aug

As an ER doctor I hate these e-bikes… Please wear a helmet Don’t drink alcohol and e-bike Don’t carry a baby while riding an e-bike Don’t e-bike after taking your blood thinners and reminiscing about your last hip fracture

17 July

Reposting this thread now that people are studying for tox boards and other tests!!! Good luck :)

Josh Trebach, MD@jtrebach.bsky.social

26 June

stop telling yourself you deserve a sensitive man you deserve a sensitive AND specific man

14 June

If the human body was an amusement park would the nephron or the semicircular canals be a better rollercoaster

2 June

friendly reminder that sometimes your patient isn’t “confused” or “altered” or “demented” they literally just need their hearing aids

27 Apr

currently in the phase of my life where all my shirts need texture

21 Apr

one time in med school I asked a doctor for feedback and he told me that I was stapling the patient lists together with the staple in the incorrect orientation and that a diagonal staple was not appropriate and it needed to be a horizontal staple so I laughed but he did not laugh

8 Apr

one time in med school we learned about a disease that gives you silver stools and I was like “woah I wonder what that looks like” so I googled it and idk what I was expecting

20 Mar

we joke in the ER that “chief complaints come in threes” so after two people came in after slipping/falling on ice i was like “okay who’s next” but a third never came in anyways i got off shift, walked to my car, and i

3 Mar

*be me in airport* me: person: hi Dr Trebach me: oh hey (who is this person? are they a patient? a student? why can’t I remember? Omg I’ve been thinking too long now it’s getting uncomfo—) person: u dropped this *hands me my hospital badge that says Dr Trebach*

11 Feb

it kind of sucks that you can randomly dislocate your jaw from yawning and then you have to go to the ER so we can pop it back into place

23 Jan

got a space heater and I was like “omg it’s so cute its saying hi to us!!” and my husband was like “no u doofus that is the power setting” 🙃

17 Jan

nothing will betray you faster than the front shirt pocket of hospital scrubs one lean forward and your pens and dignity end up on the floor

9 Jan

ER doc here. I’ve seen patients walk out during heart attacks and other life-threatening emergencies because no one could feed their pets at home. Imagine the lives saved if free emergency pet care existed.

Hi, medical toxicologist/ER doctor here 👋 here’s what you need to know about medetomidine in the illicit opioid supply

(cont.) Good supportive care is key. Acute withdrawal from the opioids should be managed the same way you would normally manage opioid withdrawal (ie, meds like buprenorphine). Medetomidine withdrawal may require introduction of alpha 2 agonists like clonidine to help manage.

I'll wrap this up here so I don't keep rambling--thanks for reading everyone. If you are concerned about yourself/someone, please call 911/go to the nearest hospital (pls do not dm/email me asking for medical advice).

Hi, medical toxicologist/ER doctor here 👋 here’s what you need to know about medetomidine in the illicit opioid supply

CAN YOU WITHDRAW FROM BOTH OPIOIDS & MEDETOMIDINE? People can withdraw from opioids which can be incredibly awful to go through. One can withdraw from medetomidine as well and experience effects like tachycardia and encephalopathy. Going through both withdrawals would be awful

HOW DO CLINICIANS TREAT WITHDRAWAL FROM OPIOID/MEDETOMIDINE? I recommend consulting with tox/poison center/addiction medicine. There's good data on opioid withdrawal treatment, but medetomidine withdrawal has less data and would benefit from expert involvement (see next tweet)

Hi, medical toxicologist/ER doctor here 👋 here’s what you need to know about medetomidine in the illicit opioid supply

WHAT HAPPENS WHEN SOMEONE USES OPIOIDS + MEDETOMIDINE? Medetomidine = sedation, bradycardias, hypotension. Some data show hallucinations. Opioids = sedation, bradycardias, hypotension, and life-threatening respiratory depression. Together these are a dangerous combination

TREATMENT FOR OPIOID/MEDETOMIDINE TOXICITY? For clinicians, treatment = supportive (protect airway, address hypotension with fluids & pressors if needed, etc), give naloxone if concern for opioid toxidrome present/respiratory depression. Calling poison control/tox is recommended

Hi, medical toxicologist/ER doctor here 👋 here’s what you need to know about medetomidine in the illicit opioid supply

WOULD SOMEONE KNOW IF THEIR OPIOIDS HAS MEDETOMIDINE IN IT? There’s no data (to my knowledge) that says medetomidine has a certain taste/smell/appearance. People may feel their normal opioid hit them harder (or cause hallucinations?) and it may lead to a new withdrawal state

CAN YOU TEST SOMEONE FOR MEDETOMIDINE? Yeah you can do testing to look for medetomidine/metabolite of medetomidine but it’s certainly not a routine test that is quickly done. Usually it would be a test that a hospital would have to send out to specific lab.

Hi, medical toxicologist/ER doctor here 👋 here’s what you need to know about medetomidine in the illicit opioid supply

SO DOES THE LEVOMEDETOMIDINE DO ANYTHING? Short version: eh Long version: the data we have shows that it doesn’t seem to be cause any effects in dogs/rats at decent dosing; however, there may be some human cell/receptor interactions in some data (PMID 9584224)?

WHY IS MEDETOMIDINE IN THE ILLICIT OPIOID SUPPLY? Not entirely clear, but possibly bc it can be used to mimic sedative effects of opioids (e.g., fentanyl) while reducing cost for suppliers. There's also market/cost factors $$$$$. Also its high potency may make it appealing

Hi, medical toxicologist/ER doctor here 👋 here’s what you need to know about medetomidine in the illicit opioid supply

WHAT IS MEDETOMIDINE? Medetomidine is a veterinary anesthetic medication. It’s composed of two different types of molecules called enantiomers: dexmedetomidine and levomedetomidine. The dexmedetomidine is the active component and is an alpha 2 adrenergic agonist.

WAIT ISN’T DEXMEDETOMIDINE A HUMAN DRUG? Ya there’s a drug called Precedex (dexmedetomidine) that is used in humans for sedation. It does not contain levomedetomidine.

14 Dec 2025

street fighter xmas sweater

7 Nov 2025

one time I was driving home and I saw a small crowd around someone who looked dead so I pulled my car over and checked for a pulse and then started cpr on the sidewalk and while I was doing cpr a bystander tried to STEAL MY CAR KEYS

3 Nov 2025

nurse: doctor josh can you please tell my son that he shouldn’t eat too much candy me: ugh yeah one time I ate so much sour candy that my tongue started peeling it was soooo painful nurse: oh wow how old were you me: …….yesterday

27 Oct 2025

one time in college I took an exam thinking “wow this is way harder than I expected” and the professor walked by and gasped because she’d given me (AND ONLY ME??) an exam from a different course. Every hard exam since I was like IS IT HAPPENING AGAIN? IT CAN’T HAPPEN TWICE RIGHT?

22 Oct 2025

people named barb are so lucky because they can be like “my name is short for phenobarbital” and no one can argue with them

18 Oct 2025

didn’t think this needed to be said but please don’t put urine in your eyes

15 Oct 2025

when I was a resident, a mysterious ER nurse used to leave a cookie on my desk after I did a good job with a sick patient. Years later, no cookies appear…but after every resuscitation I still crave one….a Pavlovian echo of a kindness that never quite left me 🍪