I've got around to confirm the hypothesis. I've had a save game from when I was about to leave the Jedi Academy, so let's make it the starting point. I used some cheats (namely turbo, revealmap and invulnerability) because I wanted to get this done quickly. None of the cheats affected the results.

Before the Kolto crisis, prices for the following items were as follows:

| Price | Item | Buy | Sell | ----------------+------+------+ Medpack | 40 | 10 | Adv. Medpack | 80 | 20 | Antidote Kit | 49 | 12 | ----------------+------+------+ Repair Kit | 25 | 6 | Adrenal Alacrity| 50 | 12 | Response Package| 1000 | 250 |

I tested the non-medpack items because I had them in inventory and are "somehow" related to healing. This is a screenshot of the buying and selling prices for Medpacks, at the first store the player finds, in Manaan.

As seen by both sources, selling prices in KOTOR are 1:4 of the buying price, being truncated when the selling price isn't an integral.

I've done the "hack passcards" approach and lastly, poisoned The Progenitor, passed the court and was banned from Manaan.

After the Kolto crisis has begun, the prices for the former items are as follows:

| Price | Item | Buy | Sell | ----------------+------+------+ Medpack | 120 | 30 | Adv. Medpack | 240 | 60 | Antidote Kit | 147 | 36 | ----------------+------+------+ Repair Kit | 25 | 6 | Adrenal Alacrity| 50 | 12 | Response Package| 1000 | 250 |

As seen, only real healing items get their price tripled. I didn't look up at how the items were later distributed across vendors, although I remember reading somewhere that the items would become scarcer as well.

Back to the point. As items get their buying and selling prices tripled, it still makes a loss, when buying healing items before the crisis. In this sense, you can't make a profit.

On the other hand, your profits have now tripled if all you do is sell the healing items that you get for free.

UPDATE: By suggestion of LessPop_MoreFizz I went ahead and looked at the prices offered by Suvam Tam, which for those that don't know, is at Yavin (which for the XBox version is a bonus content; PC, OSX and iOS is right out of the box) and specializes in some expert equipment.

He offers better selling prices than the standard vendor and if you beat him at Pazaak 10 times, he gives you a 20% discount on any item (considering his items are pricey, it's well worth it).

Selling prices with him are 65% of the item's buying price, always. Hence, the prices he offers before and after the crisis are as follows:

| Price | | B.C. | A.C. | B.C. | A.C. | B.C. - Before crisis Item | Buy | Buy | Sell | Sell | A.C. - After crisis ----------------+------+------+------+------+ Medpack | 40 | 120 | 26 | 78 | Adv. Medpack | 80 | 240 | 52 | 156 | Antidote Kit | 49 | 147 | 31 | 95 |

Suvam doesn't sell the medpacks, hence the buy prices are there for comparison. You can see that you can buy medpacks before the crisis and then selling them at Suvam after the crisis has begun will get you a 95% net profit. You can indeed profit from tainting the galaxy's medicine supply.