Shares of

Andrx

( ADRX) were among the worst-performing health-related stocks Friday, falling 12% after the company posted disappointing second-quarter results.

The generic-drug maker reported earnings of $8 million, or 11 cents a share, on sales of $259.1 million. Analysts polled by Thomson First Call were expecting earnings of 18 cents a share on sales of $270.1 million. A year ago, the company earned $6.4 million, or 9 cents a share, on sales of $290.6 million. Shares were trading down $2.49 to $18.35.

Drugstore.com

( DSCM) fell 18% after the company posted a smaller-than-expected loss during the second quarter but warned that third-quarter losses would be higher than expected. The company reported a loss of $4.3 million, or 5 cents a share, on sales of $96.9 million during the second quarter. Analysts were expecting a loss of 7 cents a share on sales of $98.1 million. A year ago, the company posted a loss of $5 million, or 7 cents a share, on sales of $87.8 million. Looking ahead, drugstore.com forecast a third-quarter loss of $7.5 million to $8.5 million on sales of $93 million to $96 million. Analysts had been expecting a loss of $4.7 million, or 6 cents a share, on sales of $101 million. Shares were trading down 76 cents to $3.43.

Shares of

Staar Surgical

(STAA) - Get Report

rose 36% after the company received an approvable letter from the Food and Drug Administration for its Myopic Visian ICL implant. The approval is contingent upon a favorable FDA inspection that finds the company's manufacturing facilities, methods and controls in compliance with the FDA's quality system regulation. The Visian ICL is a refractive phakic implant that is placed in the posterior chamber of the eye.

Separately, Staar Surgical reported a second-quarter loss of $2.1 million, or 9 cents a share, on sales of $13.9 million. Analysts were expecting a loss of 8 cents a share on sales of $13.1 million. A year ago, the company posted a loss of $3.4 million, or 18 cents a share, on sales of $12 million. Shares were trading up $1.40 to $5.27.

Community Health Systems

(CYH) - Get Report

rose 8% after the hospital operator posted second-quarter earnings that were ahead of expectations. The company posted earnings from continuing operations of $46.2 million, or 49 cents a share, on sales of $918.7 million. Analysts were expecting earnings of 45 cents a share on sales of $898.6 million. A year ago, the company earned $38.8 million, or 38 cents a share, on sales of $771.1 million. Shares were trading up $2.65 to $37.88.

Shares of

Coherent

(COHR) - Get Report

fell 11% after the company posted third-quarter results. The company reported earnings of $9.6 million, or 31 cents a share, on sales of $125.3 million. Excluding several items, the company would have reported pro forma earnings of 30 cents a share. Analysts were expecting earnings of 28 cents a share. A single analyst forecast sales of $133.4 million. A year ago, the company earned $4.7 million, or 15 cents a share, on sales of $128 million. Year-ago results included a one-time gain of $700,000, or 2 cents a share. Shares were trading down $4.27 to $33.28.

Other health-care volume movers included

StemCells

(STEM)

, up 85 cents to $6.08;

Aastrom Biosciences

(ASTM)

, up 18 cents to $3.21;

Pfizer

(PFE) - Get Report

, up 2 cents to $26.79;

Amgen

(AMGN) - Get Report

, down 58 cents to $80.42;

Ivax

( IVX), down 5 cents to $25.38;

Teva Pharmaceutical

(TEVA) - Get Report

, down 42 cents $31.52;

Elan

(ELN)

, down 5 cents to $7.45;

UnitedHealth Group

(UNH) - Get Report

, down 52 cents to $52.40;

Genzyme

( GENZ), down 59 cents to $74.61;

Millennium Pharmaceuticals

( MLNM), down 9 cents to $10.28;

Johnson & Johnson

(JNJ) - Get Report

, down 52 cents to $64.21;

Merck

(MRK) - Get Report

, down 21 cents to $31.08; and

Schering-Plough

( SGP), down 17 cents to $20.84.