Vioxx is commonly prescribed in the following doses. Follow your doctor’s advice if he suggest a different dosage, always use the minimum effective dose.

Osteoarthritis - 12.5 mg once a day, up to a maximum of 25 mg once daily.
Acute or Menstrual Pain - 50 mg once a day, for up to 5 days
Kidney Impairment: This medication is not recommended in acute kidney disease or failure.
Liver Impairment: Patients with liver disease or impairment may be prescribed half the regular dose. This medication is not recommended in acute liver disease.
Vioxx is available in the following forms and strengths:

12.5 mg, off-white tablet
25 mg, yellow tablet
50 mg, orange tablet
12.5 mg/5 mL oral suspension, white to light yellow, strawberry flavored
25 mg/5 mL oral suspension, white to light yellow, strawberry flavored