Hi there,
The are a couple of ways that I can think off on the top of my head:
1. Avoid the injection if possible i.e. consider oral medication where available
2. Use the smallest needle possible
3. Consider using a topical anaesthetic agent such as Emla cream
4. Ask an experienced practitioner to do the injection
5. Progressively infiltrate with local anaesthetic while doing the injection
Hope this helps.
BW
Dr Dinesh