Lexi-Comp Online  - Contains comprehensive drug information supplemented by specialized databases on pediatric and geriatric drugs, natural products, and drug-induced nutrition depletion.

Micromedex Healthcare Series - Contains full-text databases on chemical, pharmaceutical, and related biological substances used in clinical patient care, teratogenicity, toxicology, alternative medicine, pharmaceutical and patient information. Summary information can be downloaded to your PDA. Review Micromedex User Agreement and Password Request.  

MD Consult - Contains drug info from Gold Standard, drug news, and the latest FDA approvals.

LexiComp 
MedCalc
MerckMedicus
MicroMedex (summaries only, user name/password required)
Shots 2008

AHFS Drug Information
DrugPoints System
Ford Clinical Toxicology
Goldfrank Toxicologic Emergencies
Goodman & Gilman Pharmacology
Katzung Basic & Clinical Pharmacology
Olson Poisoning & Drug Overdose

AIDSinfo - HIV - AIDS Clinical Trials
Clinical Trials - National Cancer Institute
Centerwatch Clinical Trials
ClinicalTrials.gov

ACP-ASIM Adult Immunization Initiative
CDC Immunization Schedules  

Drug Information Portal (National Library of Medicine)

AIDSinfo - HIV - AIDS Information

Antibiotic Guide - from Johns Hopkins University provides current information about using antibiotics for the diagnosis and treatment of infectious diseases. Free registration required. PDA format available.

Antibiotic Utilization Guidelines-1997, Medical College of Wisconsin - intended to promote selective, cost effective use of antimicrobials, and to serve as Drug Use Evaluation criteria for antibiotic audits.

DrugDigest - a noncommercial, evidence-based, consumer health and drug information site.

Drugs in Pregnancy and Breastfeeding - from the Harbor UCLA Medical Center Ob/Gyn department, this guide ategorizes common drugs and drug classes by risk to pregnancy.

Electronic Orange Book - approved drug products with therapeutic equivalence evaluations.

FDA - news, drug approvals, recalls, laws, federal regulations, clinical trials information.

Hazardous Substances Data Bank - from the National Library of Medicine, focuses on the toxicology of potentially hazardous chemicals and contains information on human exposure, industrial hygiene, emergency handling procedures, environmental fate, regulatory requirements, and related areas. HSDB is organized into over 4,500 individual chemical records.

HerbMed - providing hyperlinked access to the scientific data underlying the use of herbs for health, this site is an "evidence-based information resource for professionals, researchers, and general public."

Household Products Database - from the National Institutes of Health, this database contains health and safety information on more than 2,000 ingredients in more than 4,000 common household products. It identifies products that pose health risks if they are ingested or inhaled, or if they come in contact with eyes and skin.

Lexi-Comp- New Drugs Reference Library - timely, concise, and unbiased drug information on medications recently approved by the FDA or those likely to be FDA approved within the next year.

MEDLINEplus Drug Information - this guide for consumers contains information on thousands of prescription and over-the-counter medications.

TOXNET - Toxicology Data Network National Library of Medicine site devoted to databases on toxicology, hazardous chemicals, and related areas.