Entex LA

Generic name: Guaifenesin with phenylpropanolamine hydrochloride.

Other brand names: Exgest LA, Gentab LA, Nolex LA, Vanex LA.

Entex LA is a decongestant-expectorant combination. Decongestants constrict blood vessels in the nose and sinuses to open air passages. Expectorants change a nonproductive cough into a productive cough (producing phlegm).  

Quick Facts About Entex LAEntex LA


Used to treat bronchitis, the common cold, sinus inflammation, nasal congestion, and sore throat.

Entex LA Dosage

May break tablets in half for easier swallowing; must swallow whole, not crushed or chewed.

  • Usual adult dose: 1 tablet every 12 hours.
  • Usual child dose (for children 6 to 12 years): 1/2 tablet every 12 hours.
  • Missed dose: take as soon as possible, unless almost time for next dose. If so, skip missed dose; go back to regular schedule. Do not double doses.

Entex LA Side Effects

Overdose symptoms:

coma, convulsions, high blood pressure. If you suspect an overdose, immediately seek medical attention.

More common side effects: difficulty urinating (for men with enlarged prostate), headache, inability to sleep or difficulty sleeping, irritated stomach, nausea, nervousness, restlessness.

No known less common or rare Entex LA side effects.


Do not take concurrently with MAO inhibitors such as Nardil and Parnate. Avoid Proventil, Ventolin, and many decongestants.

Inform your doctor before combining Entex LA with:

bromocriptine (Parlodel), methyldopa (Aldomet).

No known food/other substance interactions. 

Special Cautions

If pregnant or planning to become pregnant, inform your doctor immediately. Not known if Entex LA appears in breast milk.

No special precautions apply to seniors.

Follow doctor’s instructions carefully for children 6 to 12 years.

  • Inform your doctor before taking Entex LA if you have: diabetes, heart disease, or high blood pressure.
  • Should not use if sensitive to other stimulants such as Dristan Decongestant.
  • Use with caution if you have: glaucoma, hyperthyroidism, or prostate enlargement.


HealthSurvey.org provides accurate and independent information prescription pills, over-the-counter medicines and natural products. This material is provided for educational purposes only and is not intended for medical advice, diagnosis or treatment. If you have questions about  dosage, or Entex LA side effects, please contact your healthcare provider.