Health stocks were weaker Monday, with the Nasdaq biotechnology index down 1.5% and the Amex biotechnology index off 0.9%.

Among individual stocks, notable movers were:

Molecular Insight

( MIPI), up 9.7% at $4.18

Mentor

( MNT), up 8% at $15.94

Amylin

( AMLN), up 7.8% at $6.91

Theravance

(THRX)

, up 6.8% at $6.58

Alexion Pharmaceuticals

(ALXN) - Get Report

, up 3.8%, at $39.69

United Therapeutics

(UTHR) - Get Report

, down 35.2% at $58.62

Intuitive Surgical

(ISRG) - Get Report

, down 16.9% at $123.34

Merck

(MRK) - Get Report

, down 4.9% at $25.99

Amgen

(AMGN) - Get Report

, down 3.7% at $56.09

Wyeth

( WYE), down 3.7% at $32.89

This article was written by a staff member of TheStreet.com.