IMPORTANT: Please consult your physician or pharmacist for dosage requirements, and more information regarding your personal use, before using any of the substances discussed below.

A brief look at pain-killers and their use in endurance sports
Most of us have done it at some time or other. When the agony of hamburger feet is slowing you to a crawl and you begin rationalizing the DNF option, there’s nothing like a handful of painkillers to keep you moving. There are times when pharmaceuticals are a racer’s best friends, but we have to remember: these are drugs that we are popping, not M&Ms™.

Any widely available pharmaceutical, whether prescription or over-the-counter, has gone through rigorous testing to ensure that it’s safe. Even so, some will have drug interactions, many will have side-effects, most will have contraindications, and almost all have a maximum safe dosage. The rest of this article will present the bare-bones facts about the most common pain-killers so you can use them safely and effectively.

Notes and Definitions
Most of these drugs require that they be stored at something like room temperature, in a dry environment. This is not always feasible during a race; however it appears that as long as they are kept dry, these drugs will not be compromised by colder or hotter storage for a few days.

All of these drugs have a shelf life. The “best before” date should be written on the bottle, so make sure you keep track of it. Some races have very thorough medics doing gear checks, and they won’t sign off on your first aid kit if you have expired drugs – good on them. Ask your pharmacist about how to dispose of old drugs that have passed their shelf lives.

Contraindications: A condition which makes a particular treatment or procedure inadvisable.

Drug interactions: Whenever two or more drugs are taken together, there is a chance that there will be an interaction among them. This may increase or decrease the effectiveness and/or the side effects of the drugs, or may result in entirely new side effects.

NSAID: the acronym for Non-Steroidal Anti-Inflammatory Drug. As a group, NSAIDs are non-narcotic relievers of mild to moderate pain, fever, and inflammation.

Important Disclaimer Stuff
While everything written here has been proofed by a medical doctor, an exercise physiologist, and a pharmacist please remember that every person and situation is unique. An adventure racer in the middle of a race is not typical of the test subjects used to determine drug safety. Racers are dehydrated or heat exhausted or hyponatremic or hypothermic, likely all at the same time. They are often taking the maximum daily dosage of several of these drugs, sometimes for days at a time. If you have any concerns, please consult your physician and/or pharmacist.

The old rule of “never try anything new during a race” applies here in spades. If you’re planning to use any of these drugs for the first time, make sure you test it out in training first. Being in the middle of the wilderness is not the time to see if you have any serious adverse reactions.   Ok, here we go…

ASPIRIN
Also know as acetylsalicylic acid or ASA, aspirin belongs to the NSAID group of drugs. It is used for the treatment of inflammation that results from many forms of arthritis, osteoarthritis, as well as soft tissue injuries, such as tendonitis and bursitis. Aspirin is also used for rapid relief of mild to moderate pain and fever. Because aspirin inhibits the action of blood clotting elements, it is used to reduce the risk of recurrent stroke and to prevent heart attack.

Dosage
The maximum dosage is 650 mg 4 times per day in cases of severe stroke risk, but most people cannot tolerate this dose due to gastrointestinal distress. Aspirin should be taken with meals.

Contraindications / Drug Interactions
Aspirin should be avoided by people with peptic ulcer disease or poor kidney function, since it can aggravate both conditions. It should also be avoided by people taking blood thinning medications such as Warfarin, because of an increased risk of bleeding. People with anemia should also avoid aspirin for this reason. Some asthma patients can have worsening of breathing while taking aspirin. Aspirin can alter the blood uric acid level and is avoided in patients with hyperuricemia and gout. Aspirin can increase the effect of medicines used to treat diabetes mellitus, resulting in abnormally low blood sugars if not monitored. Aspirin is generally avoided during pregnancy and in nursing mothers.

Side Effects
Most people benefit from aspirin with few side effects. However, serious side effects can occur, mostly with higher doses. Therefore, try to use the lowest effective dose to minimize side effects. The most common side effects of aspirin involve the gastrointestinal system and ringing in the ears. It can cause ulcerations, abdominal burning, pain, cramping, nausea, gastritis, and even serious gastrointestinal bleeding and liver toxicity. Sometimes, stomach ulceration and bleeding can occur without any abdominal pain. Black tarry stools (that’s medical lingo for “poo”), weakness, and dizziness upon standing may be the only signs of internal bleeding. Should ringing in the ears occur, the daily dose should be reduced. Rash, kidney impairment, vertigo, and light-headedness can also occur.

Verdict: As an adventure racer, aspirin should be your pain-killer of last resort. It has the strongest blood-thinning action, which causes increased bleeding when you get cut, scraped, and bruised. Note that I said “when” and not “if”. Also, mg for mg aspirin is the most likely to cause stomach erosion. Use it only if you can’t tolerate acetaminophen or other NSAIDs.

IBUPROFEN
Ibuprofen is another NSAID, and is found in common over-the-counter products such as Advil and Motrin. Like aspirin, it is used to treat mild to moderate pain, inflammation, and fever.

Dosage
For mild to moderate pain, menstrual cramps and fever the usual adult dose is 200 or 400 mg every 4 to 6 hours. Arthritis is treated with 400 to 800 mg 3 or 4 times daily. The maximum dose is 1200 mg daily. Individuals should not use ibuprofen for more than 10 days for the treatment of pain or more than 3 days for the treatment of a fever unless directed by a physician. Ibuprofen should be taken with meals.

Contraindications / Drug Interactions
People with pre-existing impairment of kidney function or congestive heart failure should use ibuprofen and other NSAIDs cautiously. People who are allergic to other NSAIDs, including aspirin, should not use ibuprofen. Individuals with asthma are more likely to experience allergic reactions to ibuprofen and other NSAIDs.

Ibuprofen may increase the blood levels of lithium and possibly lead to lithium toxicity. Ibuprofen may reduce the effectiveness of drugs that are given to reduce blood pressure. When ibuprofen is used in combination with aminoglycosides the blood levels of the aminoglycoside may increase. This may lead to aminoglycoside-related side effects. Individuals taking oral blood thinners should avoid ibuprofen because it also thins the blood, and excessive blood thinning may lead to bleeding.

There are no adequate studies done on ibuprofen during pregnancy, so it is best avoided. Nursing mothers should also avoid taking ibuprofen and NSAIDs in general.

Side Effects
The most common side effects from ibuprofen are rash, ringing in the ears, headaches, dizziness, drowsiness, abdominal pain, nausea, diarrhea, constipation and heartburn. Ibuprofen may cause ulceration of the stomach or intestine, and the ulcers may bleed. Sometimes, ulceration and bleeding can occur without abdominal pain, and black tarry stools, weakness, and dizziness upon standing may be the only signs of a problem.

Verdict: Ibuprofen is a better option than aspirin because it won’t thin out the blood as much and won’t aggravate the gastrointestinal tract to the same extent. Try ibuprofen products if you cannot take acetaminophen.

ACETAMINOPHEN
Acetaminophen, unlike aspirin and ibuprofen, is not a NSAID. It belongs to a class of drugs called analgesics (pain relievers) and antipyretics (fever reducers). The most common over-the-counter acetaminophen products are Tylenol and Excedrin (the non-ASA variants).

Acetaminophen is used for the relief of fever and pain associated with many conditions. It was thought to have no effect on underlying inflammation, and was therefore not used for arthritic conditions. However, there have been some recent indications that it may have some anti-inflammatory properties.

Dosage
The regular dose for adults is 325 - 650 mg every 4-6 hours. The maximum daily dose is 4000 mg.

Contraindications / Drug Interactions
Acetaminophen is metabolized by the liver. Therefore drugs that increase the action of liver enzymes that metabolize acetaminophen may decrease its effectiveness. The potential for acetaminophen to harm the liver is increased when it is combined with alcohol or other drugs that also harm the liver. Acetaminophen is used in all stages of pregnancy, and its use by nursing mothers appears to be safe.

Side Effects
When used appropriately, side effects are rare. The most serious side effect is liver damage due to large doses, chronic use or combination with alcohol or other drugs that also damage the liver.

Verdict: Acetaminophen should be the adventure racer’s pain killer of choice. It is as effective a pain killer as aspirin or ibuprofen, but without two important side effects: it doesn’t thin the blood, and it doesn’t cause gastrointestinal tract distress.

CODEINE
Codeine is a narcotic pain reliever that is frequently combined with Tylenol or aspirin for more effective pain relief. It is a prescription drug that is generally not available over-the-counter. It is prescribed for the relief of mild to moderately severe pain. Common brand names include Empirin #2, 3, 4; Tylenol #2, 3, 4; Tylenol with Codeine Elixir.

Dosage
Always follow the dosage directions on the prescription.

Contraindications / Drug Interactions
Tylenol with codeine tablets contain a sulphite that can cause allergic asthma or even life-threatening anaphylaxis reactions in susceptible patients (more frequently in asthmatic patients).

Codeine can impair thinking and the physical abilities required for driving or operating machinery – or mountain bikes. Alcohol and other sedatives can produce further brain impairment and even confusion when combined with codeine, and should therefore be avoided. Codeine may be habit-forming. Mental and physical dependence can occur, but are unlikely when used for short-term pain relief.

Codeine should be avoided during pregnancy and in nursing mothers.

Side Effects
The most frequent side effects include light-headedness, dizziness, nausea, vomiting, shortness of breath, and sedation. Other side effects include allergic reactions, constipation, abdominal pain, and itching.

Verdict: Codeine pain killers should never be taken during a race. It’s only role in adventure racing might be as temporary, emergency pain relief if you’ve been seriously hurt and are waiting to be evacuated from the course.

WRAP UP
Hopefully this article has given you the information you need to decide if, when, and how to use pain-killers during races. The final determinant should be how your body reacts, not what is written here or even on the packaging.

Pain-Killers: Addendum
I got a couple of additional tidbits from Dr. Mark Tarnopolsky (Team LSN, formerly EAS) via Barb the TreeHugger (thanks, Barb!):
Be cautious with anti-inflammatories like Motrin or Advil:

- If you’re dehydrated, they can make things worse, potentially leading to kidney
  damage. (Reminder: Never get dehydrated!)

- Exercise diverts blood flow from the gut, reducing it by up to 70%. This in turn reduces
  your natural protection against ulcers, reflux and small hemorrhages.
  Thus in a race, anti-inflammatories have an increased risk compared to using them in
  your day-to-day life, so don’t take them without a reason.”

I have to say a big “thank you” to Dr Tarnopolsky for taking the time to read over my first draft and making sure there was no misinformation or serious omission.

IMPORTANT: Please consult your physician or pharmacist for dosage requirements, and more information regarding your personal use, before using any of the substances discussed above.