Book about dragons blood that heals

Possibly "The Blood of a Dragon" by Lawrence Watt-Evans (1991)? It's the fourth book in his Ethshar setting, but the books are almost all standalones, not part of a continuing plotline.

The story follows Dumery, a young boy who longs to learn magic, but is one of the rare people who has absolutely no talent for any of the many forms of magic. He's hurt and angry, and when he he sees a wizard humbling himself before a hunter selling dragon's blood (a vital ingredient in many spells, including eternal youth spells), becoming a dragon hunter seems like the perfect solution. The hunter turns down Dumery for an apprenticeship, too, but the boy runs away from home and doggedly follows the man to his remote home, where he proves to actually be a dragon farmer and not a hunter at all.

Original cover:

This sounds similar to The Obsidian Chronicles Trilogy by Lawrence Watt-Evans.

The story is about a young boy who drinks a mixture of blood and Dragon's venom during a Dragon attack that kills his entire family and town. He is the sole survivor but ends up enslaved afterwards. However, he receives long-life and extraordinary healing from drinking the blood / venom mixture. After escaping slavery, he sets out to revenge himself upon the Dragons and the people who enslaved him after the attack. Along the way he discovers there is more to the Dragon attack and the Dragon blood than it initially appears and his vengeance starts to bring wild magic back to the world.

The three books are:

• Dragon Weather
• The Dragon Society
• Dragon Venom

The timing is significantly off, but Robin Hobb's The Dragon Keeper (2009) covers the plot points mentioned.

The healing properties of Dragon Blood are central to the motivations of one of the characters. He's attempting to obtain some dragon blood in order to sell it to the ruler of a nearby country who is old and ill, and believes it can restore him to youth and health.

Additionally all the Keepers are over the course of the story changed physically by prolonged contact with "their" Dragons. While this doesn't convey "Powers" per se, it is a significant factor in these people becoming, taller, more attractive and more intune with the Dragons they care for.

How about The Secret of Dragonhome by John Peel?

The book is a fantasy book about two siblings - Melayne and Sorrow - who have been hidden away by their parents all their life because of their special abilities that are caused by dragons blood and scales in the soil near their home.

When their parents are murdered, the leave their home only to eventually find out that the kingdoms are making pretend wars with each other and forcefully drafting people with abilities to kill them off after spending centuries killing all the dragons to stop more people from developing abilities.

The original was a stand-alone novel in 1990's.