Inhaled isopropyl alcohol for nausea

An elderly male presents to the emergency department with complaints of nausea, vomiting, and diarrhea starting a day and a half ago.  The diarrhea started abruptly, has occurred almost 10 times, and is non-bloody.  His abdomen is soft but has mild diffuse tenderness.  Vital signs and basic laboratory results are normal except for a potassium of 2.9 mEq/L and an EKG with a QTc interval of 490 msec. 
The patient is diagnosed with viral gastroenteritis and rehydration for supportive care is initiated.  What is a viable strategy to treat this patient's nausea?

Isopropyl alcohol for nausea

Though awareness is generally low, there is evidence that inhaling isopropyl alcohol is effective for relieving nausea in a variety of clinical settings, such as:  

• A 2018 Cochrane review found that inhaled isopropyl alcohol improved post-operative nausea and the need for rescue anti-emetics¹
• A 1998 study found that nausea during transport from a recovery room to a patient's room could be treated so well by inhaling isopropyl alcohol that the hospital's transport team now all carry alcohol pads²

Isopropyl alcohol in the emergency department

The newest evidence is a randomized, blinded, placebo-controlled trial in the emergency department involving adult patients presenting with nausea (≥3 out of 10) or vomiting3.  Those with an allergy to ondansetron, inability to inhale through the nose, history of prolonged QT interval, or suspicion of serotonin syndrome were excluded.  Patients were divided into three groups: (1) inhaled isopropyl alcohol + oral ondansetron 4 mg, (2) inhaled isopropyl alcohol + oral placebo, or (3) inhaled placebo + oral ondansetron 4 mg. The primary outcome was the change in nausea from baseline to 30 minutes post-intervention using a 0-100 mm visual analog scale (VAS).  Zero was no nausea and 100 was the worst nausea imaginable. One-hundred and twenty patients completed the study and the main results can be found in this table:

Variable	Inhaled alcohol + ondansetron (n = 40)	Inhaled alcohol + placebo (n = 40)	Inhaled placebo + ondansetron (n = 40)
Symptom duration (h)	13.5	24	19
Initial nausea score (mm on VAS)	53	51	51
Nausea reduction at 30 minutes (mm on VAS)	30 (95% CI 22-37)	32 (95% CI 25-39)	9 (95% CI 5-14)
Received rescue anti-emetic therapy after 30 minute primary outcome (%)*	27.5	25	45

*Of note, no subjects received rescue antiemetics before the 30 minute primary outcome was assessed

From the above table, we can see that subjects who were randomized to either of the inhaled alcohol groups achieved statistically significant reductions in nausea relative to the ondansetron monotherapy group (a reduction of around 30 mm on the VAS!).  Patients that only received ondansetron required more rescue anti-emetic therapy (45%).  Also assessed (but not on this table), patients that received the inhaled isopropyl alcohol had higher satisfaction scores, better pain relief, and better nausea scores at discharge.

If thinking of applying this relatively novel treatment to your patients, it is helpful to know that the presumed causes for nausea in this study were:

• Infectious gastroenteritis (55.2%)
• Food poisoning (8.6%)
• Urinary tract infection (5.2%)
• Headache (3.4%)
• Other infective illness (3.4%)
• Gastroesophageal reflux (3.4%)
• Others (all each less than 3.4%) - constipation, electrolyte disturbances, appendicitis, gallbladder disease, medication reaction, pelvic inflammatory disease, vertigo, other

Instructions for inhaling isopropyl alcohol

1. Obtain isopropyl alcohol pads (common, cheap, commercially available over-the-counter)
2. Open pad (or have patient open pad) and hold 1-2 cm from nose
3. Inhale deeply through nose as frequently as required to relieve nausea
4. Repeat every 10 minutes as necessary (with a new pad)

Back to the patient case

In the above case, the patient is presenting with nausea likely secondary to viral gastroenteritis.  General supportive care with hydration is warranted.  Improving symptoms and correcting electrolyte abnormalities is also warranted.  This patient's age, hypokalemia, and prolonged QTc make ondansetron an undesirable option for nausea.  Inhaled isopropyl alcohol is a viable alternative option given the small but compelling body of evidence, especially considering its rapid effect, lack of adverse effects, low cost, ease of use, and widespread availability.  Utilizing this alternative could have substantial impact as ondansetron was the most used drug in the emergency department in 2015 according to the CDC (only behind sodium chloride).4

Take home points

• Inhaled isopropyl alcohol was more effective for nausea compared to ondansetron in the emergency department - by about 30 mm (small but compelling study)
• Most patients had viral gastroenteritis
• Isopropyl alcohol pads are readily available, cheap, quick, and have no adverse effects
• To use, hold 1-2 cm from nose, inhale deeply, and repeat as needed

References
1.  Hines S, Steels E, Chang A, et al. Aromatherapy for treatment of postoperative nausea and vomiting  Cochrane Database of Syst Rev 2018
2.  Smiler BG.  Isopropyl alcohol for transport-related nausea  Anaesth Analg 1998;87:1211.
3. April MD, Oliver JJ, Davis WT, et al.  Aromatherapy versus oral ondansetron for antiemetic therapy among adult emergency department patients: A randomized controlled trial  Ann Emerg Med  2018.
4.  Rui P, Kang K. National Hospital Ambulatory Medical Care Survey: 2015 Emergency Department Summary Tables. Available from: http://www.cdc.gov

image by David Goehring