Will I be covered by travel insurance if the injury is alcohol related?
No. This is a standard exclusion in travel insurance policies. Basically, it states that injuries or losses suffered while under the influence of alcohol (or drugs) are excluded from coverage.
It only makes sense that an insurance company needs to exclude injuries sustained while intoxicated; the risk for injury is much higher when drinking; similar to the higher risk associated with hang-gliding, skydiving, or motor sports.
This story about a young Canadian man on vacation is a perfect illustration: after arriving in Mexico, he and two friends celebrated with several drinks. He fell 7 stories off the balcony of his hotel, and sustained multiple injuries. He did not remember exactly what happened, but admitted that drinking was involved.
Unfortunately for the young man, his medical expenses will not be covered, even though he had purchased a travel insurance policy.
This illustrates the need for common sense and caution. All travel insurance policies have exclusions for high risk activities. Read your travel insurance policy and make sure you understand what is covered and what is not covered.