Back in July, I was positive on shares ofPfizer (PFE) - Get Report . I thought the company was executing exceptionally well. Then, the stock took a dive.

Now what?

In early August, Pfizer reported an OK quarter. The company said it earned 64 cents per share, 2 cents better than the consensus estimate. Revenue rose 10.9% to $13.15 billion. Management reaffirmed guidance for fiscal 2016. The stock dipped because management didn't provide any update on its

Essential Health

spinoff.

Then, on Aug. 22, the company announced it would acquire Medivation (MDVN) , a biotech company focused on commercializing small molecules for oncology. Pfizer paid $81.50 a share in cash for a total of $14 billion -- a stiff 38 times 2017 estimates for the company. Management hopes the deal will jump-start its growth.

The high price Pfizer paid for Medivation only confirmed investors' view that Pfizer is desperate for growth. Investors freaked out and hit the sell button on the news.

Then, a few weeks later, management really dropped a bomb. The company said it would not split its Essential Health unit from its Innovative Health division. The two divisions operate separately and investors had expected the company to spin off the slower-growing, lower-margin EH business.

Essential Health is Pfizer's portfolio of older products and generic treatments. Off-patent drugs like Lipitor saw sales drop 8% to $422 million and Premarin sales fell 7% to $244 million. Last quarter, the EH unit posted sales of $5.7 billion, up 7%, but that includes $3.4 billion of "other" sales that were up 24%.

The failure of the company to spin off the Essential Health division was a major disappointment for investors because they assumed a spin would act as a major catalyst for Pfizer shares. The stock was pounded lower again.

And on Wednesday, Reuters said Pfizer might be investigating the sales of its "other" business, also known as the Consumer Health Division. Consumer Health sells Chapstick lip balm and Advil painkiller, among other things. According to Reuters, the division could fetch $14 billion.

The possibility of the Consumer Health unit spilt drove the stock higher as investors were encouraged that there could be another catalyst for the stock.

Pfizer shares are like riding a roller coaster.

At this point, I would avoid the whole situation. I think Pfizer is fairly valued. The Essential Health business is about 43.7% of total revenue. The Consumer Health business is about 60% (or $3.4 billion) of the Essential Health ($5.7 billion) division. Consumer Health would be a smaller deal, so it's probably not enough to boost the shares much higher. 

At $33, the stock is trading at 12.6 times the consensus forward estimate of $2.61, or between the valuation of generic drug company and a branded company. For example, generic drug maker Teva (TEVA) - Get Report is trading at 7 times forward estimates, and branded drug maker Abbott Labs (ABT) - Get Report is trading around 16 times, which leaves Pfizer stuck in the middle.

If Pfizer doesn't sell its Consumer Division, the stock will sink back down. I would stay on the sidelines.

This article is commentary by an independent contributor. At the time of publication, the author held no positions in the stocks mentioned.