Scuba Survey Results: Medications & Drugs in Diving
In Fall 2026, we conducted an exploratory survey of scuba divers about medications and drugs used in scuba diving.
InDepth Magazine and the Business of Diving Institute collaborate on a series of scuba diving industry surveys to better understand where we stand on dive industry issues, identify workable solutions, increase awareness of opportunities, and, most notably, fuel discussions among dive professionals.
We thank the following scuba diving industry leaders for directly supporting this initiative: DAN Europe and GUE. We also thank all of you who took part in these surveys and studies.
This post is part of our Dive Industry Compass series by the Business of Diving Institute and Darcy Kieran, author of:
Table of Contents
TL;DR Overview
Our exploratory survey reveals a critical disconnect between official dive industry guidelines and real-world diver behavior: 74.6% of surveyed scuba divers and dive professionals admit to having dived under the influence of medications or drugs.
Many of these cases involve over-the-counter (OTC) pain relievers (55.3%), decongestants and antihistamines (51.8%), and motion-sickness remedies (41.2%), though significant percentages report diving on cardiovascular medications (31.0%), psychiatric drugs (22.5%), and prescription painkillers or cannabis.
Alarmingly, 21.9% of divers admit to intentionally omitting medication use on diver medical questionnaires out of fear of being disqualified from diving. Furthermore, 45.0% never discussed medical contraindications with a physician, 92.3% never consulted Divers Alert Network (DAN), and 67.4% entered the water without informing their dive buddy.
A major operational conflict exists around decongestants: while 85.1% of decongestant users took them specifically to make diving possible or comfortable, instructors highlight a “do as I say, not as I do” culture driven by agency rules and economic pressure to keep working. These findings underscore a need for training agencies and dive centers to shift from legalistic blanket prohibitions toward realistic, evidence-based medical education and open dialogue.
Medications & Drugs in Scuba Diving – Detailed Survey Results
Have you ever gone scuba diving while under the influence of medications (including prescribed and over-the-counter medications) or illicit drugs?
74.6% of survey respondents answered yes.
Positive answers by groups:
- Dive instructors & divemasters: 71.9%
- Tech divers: 76.6%
- Recreational divers: 72.3%
- USA: 73.4%
- Western Europe: 71.6%
Have you ever voluntarily canceled a dive because you were on medications or drugs?
- Yes: 27.7%
Have you ever been advised not to dive (e.g., by a dive professional) because you were on medications or drugs?
- Yes: 13.1%
Have you ever omitted to indicate that you took medications or drugs on a diver medical questionnaire by fear of not being allowed to dive?
- Yes: 21.9%
Questions for Those Who Answered ‘Yes’ to Having Gone Scuba Diving Under the Influence of Medications or Drugs
What categories of medications or drugs have you ever been under the influence of while scuba diving? (Select all that apply)
- Over-the-counter anti-inflammatory, pain & fever medication (e.g., Tylenol, Advil, Aspirin): 55.3%
- Antihistamines & decongestants: 51.8%
- Motion-sickness & anti-nausea medication: 41.2%
- Cardiovascular medication & blood thinners: 31.0%
- Psychiatric medication: 22.5%
- Antibiotics & medication for active infections: 17.0%
- Hormonal, gastrointestinal, corticosteroid & immune-system medication: 16.3%
- Weight-loss medication: 15.7%
- Erectile-dysfunction medication: 12.9%
- Diabetes medication: 11.2%
- Respiratory medication (e.g., for asthma): 8.1%
- Recreational cannabis: 6.1%
- Prescribed painkillers (e.g., opioids): 5.0%
- Migraine and anti-seizure medication: 4.8%
- ADHD medication: 4.6%
- Illicit drugs (e.g., cocaine): 3.5%
- Prescription cannabis: 2.7%
- Sleeping medication & sleep aids: 1.8%
- Other: 4.4%
Did you discuss the contraindications of these medications or drugs for scuba diving with a doctor?
- Yes, for all: 32.8%
- Yes, for some: 22.1%
- No: 45.0%
Did you discuss the contraindications of these medications or drugs for scuba diving with a pharmacist?
- Yes, for all: 4.6%
- Yes, for some: 6.9%
- No: 88.5%
Did you discuss the contraindications of these medications or drugs for scuba diving with a representative from DAN (Divers Alert Network)?
- Yes, for all: 3.1%
- Yes, for some: 4.6%
- No: 92.3%
Looking back, do you consider it was safe for you to dive under these medications or drugs?
- Yes, for all: 83.3%
- Yes, for some: 12.1%
- No: 4.5%
Have you ever gone scuba diving while on medications or drugs without letting your dive buddy know?
- Yes: 67.4%
When you went scuba diving while on medications or drugs, did they have a negative impact on the dive or your health during or after the dive?
- Yes: 5.3%
About Scuba Divers Who Have Used Decongestants for Scuba Diving
Were the decongestants specifically taken to make diving possible or more comfortable?
- Yes: 85.1%
Did you discuss the contraindications of these decongestants for scuba diving with a doctor?
- Yes: 31.3%
Did you discuss the contraindications of these decongestants for scuba diving with a pharmacist?
- Yes: 7.5%
Did you discuss the contraindications of these decongestants for scuba diving with DAN (Divers Alert Network)?
- Yes: 4.5%
Comments From Dive Instructors Who Have Used Decongestants for Scuba Diving
Please comment. You’ve indicated that you have done scuba dives while using decongestants. Does your dive training agency provide guidance on using decongestants (official training materials from many dive training agencies teach scuba divers never to use decongestants while diving)? What do you teach your students? Do you stick to the official materials from the training agencies? Do you let your student divers know that you use decongestants? How often do students ask for advice about decongestants?
- The PADI material is prepared by lawyers, and we shouldn’t take medical advice from lawyers (they say ‘no’ to everything just to protect their rear end).
- No guidance for using from the training agencies – they all say “generally no”. But if you discuss it with active diving doctors, you get a differentiated picture. And if you listen to discussions in the diving community, using decongestants is very widespread. So it would be more realistic for the agencies to look at which ones could be used under which conditions, rather than just saying no, but knowing that many divers will still use some and experimenting themselves with the type.
- I make it clear that the official recommendation is not to dive on decongestants, but also make it clear that I do so at times. “Do as I say, not as I do”
- They say you should not; however, as an instructor, you need to be able to dive
- My training agency includes information in the student training material to avoid diving while congested or with a cold. I teach my students that decongestants and diving don’t mix. (I had visual disturbances once while taking 24-hour Sudafed, over 11 years ago. I have never taken a decongestant before diving since then.) As I haven’t taken a decongestant before diving in over 11 years, I tell my students that decongestants can be very unsafe while diving, that they can result in reverse blocks, increase blood pressure, increase the risk of DCS, and create a lot of free radicals which may not be handled without sufficient antioxidants in the body. I’d estimate approximately 5% of my students have asked about using decongestants before diving.
- Stuck to official material
- I generally find that travelling leaves me a little stuffed up, and I also find that repetitive dives can also cause strain on the sinuses. I find if I take a decongestant (tylenol cold or flu) the night before a dive, and then right before a dive, I have zero problems for the rest of the trip. It just clears everything out.
- I never recommend students take anything right before a dive, but I have suggested they take one the night before their first dive if they are known to have a similar issue, or if it’s their first time diving in the pool, I sometimes recommend a tylenol cold overnight between their two days of their course. We always review the training agency’s official guidance, and explain the risks of diving while on medication. Students often ask about diving on meds, and while I don’t lie about my own use of tylenol cold/flu, we always discuss official guidance and also direct them to DAN resources.
- This is one of the situations that I swear by, in the sense that I know a tylenol cold will fix a lot of equalization issues if taken the night before a dive and I have found these issues just do not return for most students.
- While I never tell my students to dive on medication, I myself definitely do for repetitive dives. I’ve never had issues from this, and have in fact seen much benefit and much less strain while equalizing on repetitive dives.
- I recommend to my student to seak medical support before considering taking anti-congestant and diving, preferable from hyperbaric doctors used to deal with divers
- My training agency does not have guidelines. I teach students that they should follow guidance from their doctor and DAN and not dive within a day of taking sudafed or similar decongestants. I do not tell students if I take decongestents, but I do tell other instructors and assistants. I more often use guifenasen than decongestents. Probably 1 in 5 students ask about decongestents.
- I advise students to discuss with their doctor and point them to DAN resources. While I did not discuss every single use of decongestants with a doctor or pharmacist, I did discuss the use of them multiple times with relevant professionals.
- If students ask about decongestants I tell them to check with their doctor and to call DAN. Students very rarely ask about decongestants. I do not share that I take decongestants with my students.
- I have used decongestants in the past (10+ years ago) during diving. However, due to the more recent studies on the rebound effect of decongestants I no longer use them the day of diving and warn my students about them as well.
- The agency strongly discourages the use of decongestants. This it what I tell my students. They ask regularly However realistically calling in sick is often not an option. So I let my DMs know if I have to take them, not the students.
- All questions about decongestants are answered according to the recommendations of my certifying agency. (PADI) For any questions that deviate from those recommendations, I refer the student to either their doctor or DAN.
- I have received recommendation that it’s bad due to change in ear/synuses equalization so I risk only with mild symptoms. What I am worried about is the influence some meds (with pseudoephedrine) can have on heart. To my students, I suggest general ear and nose hygiene but also recommend not using decongestants (as per standard).
- I teach them never to use decongestants, but from my experience, mild decongestants are ok if you are not seriously ill
- I Teach not to do it. Also my agency does not recommend This. My nose was not completely closed, no Hard cold.
- No / Never / Yes / Yes / Quite often from new divers, but i do not recommend them to do so
- I advise students and all customers to avoid diving while using decongestants. However, I did not always practice as I preach. For roughly 3 to 5 days I routinely used decongestants prior to diving as a means to continue working. I did this with the full knowledge and encouragement of general management and the course director that trained me to become an instructor. In fact they were the ones who suggested it in the first place. I do not place blame on others to absolve myself, however I did let advice from others influence my decision making. I now work for a dive centre with management that allows me to take a day off work if I’m too congested to equalise. I’m happy I chose to make the change. I would like to be more specific about the dive centre in question as they are one of the biggest dive centres in Indonesia, with perhaps the largest professional course enrolment region-wide. Perhaps that’s better left for later.
- For students I always tell them to consult a doctor for their own specific medical situation. I will never give a student any sort of recommendation or guidance on taking medication other than to refer them to a doctor.
- The materials talk about the risks of using decongestants. That is what I talk about when I’m teaching. No I don’t tell students if I am taking decongestants. We do sometimes have discussions around them, but I like to treat my students like the adults that they are.
- Only used it to get out of a cave on the way out. Would never start a dive on one.
- PADI says do not use decongestants, which is what i teach student divers. I have used decongestants only a few times on “fun” dives, non-teaching.
Who Participated in Our Exploratory Survey on Medications and Drugs in Scuba Diving?
708 scuba divers participated in our survey on medications and drugs in scuba diving. Thank you!
- 54.5% of them were dive instructors or divemasters.
- 53.1% of them were tech divers.
Age groups of survey respondents:
- 1928-1945 (The Silent Generation): 0.0%
- 1946-1954 (Boomers I): 9.6%
- 1955-1964 (Boomers II/Generation Jones): 19.2%
- 1965-1980 (Generation X): 32.2%
- 1981-1996 (Millennials): 31.1%
- 1997-2012 (Generation Z): 7.9%
Geographic region of residence of survey respondents:
- Western Europe: 35.6%
- United States (including AK & HI): 33.9%
- Mexico, Central America, Caribbean, Tropical Atlantic: 6.5%
- Eastern Europe (including Russia): 5.5%
- Australia, New Zealand: 4.9%
- Canada: 4.7%
- South Pacific, Indo-Pacific, Other Tropical Asia-Pacific Region (incl. Maldives): 4.6%
- Middle East (including Egypt): 2.3%
- South America: 1.1%
- Africa, Madagascar: 0.6%
- Japan, Other Non-Tropical Asia-Pacific Region: 0.2%
- China, Hong Kong, Macau: 0.1%
A very special and big “Thank You” to DAN Europe and GUE for supporting our market research efforts in collaboration with InDEPTH magazine.
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Have a look at more scuba diving market research, surveys, reports & statistics in Your Dive Industry Compass.
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Strategies for Today’s Scuba Divers
Living The Scuba Dream
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