Q Flex

1 What is Q Flex?

Brand: Q Flex, Acuflex, Beflex, Dologen, Dologesic, Relagesic, Rhinoflex, Staflex, Vistra, Zgesic, Q- Gesic

Generic: Acetaminophen and Phenyltoloxamine

Q Flex is a pain reliever, antipyretic (anti- fever) and antihistamine drug, used to treat symptoms of flu, common cold, and seasonal allergies. This is a drug combination of acetaminophen and phenyltoloxamine.

Acetaminophen relieves pain and decreases high body temperature or fever.

Phenyltoloxamine decreases the effects of histamine, a natural substance produced by the body that causes itching, runny nose, sneezing and watery eyes.


Read your medication guide and follow your doctor’s prescription at all times.

  • Take Q Flex orally/ by mouth before or after meals whenever necessary or as needed per doctor’s prescription.
  • Do not break, chew or crush sustained- release form of Q Flex to prevent releasing the content of this medication all at once, which may intensify side effects.
  • The dosage depends on your medical condition or treatment response. Do not adjust your dose without your doctor’s recommendation.
  • Do not take MAO inhibitor drugs 2 weeks before, during and 2 weeks after your Q Flex treatment.
  • Avoid alcohol intake and activities that require mental alertness (i.e. driving, operating machinery) because this medication can cause dizziness.
  • Do not take other medications that may contain acetaminophen (i.e. cold- and- flu products) without your doctor’s approval.
  • Continue using this medication on a regular schedule (same time of the day) unless you are taking it just whenever necessary only. Do not stop taking this medication abruptly without consulting your doctor.

Inform your doctor immediately if your condition aggravates, does not improve or you have a fever for more than 3 days.

Do not give this medication to children below 4 years old.

Take your missed dose as soon as possible if you are taking this medication on a regular schedule (not whenever necessary or as needed only). However, make sure that the time interval between the missed and the next dose is not too close.

Otherwise, stick with the regular schedule and leave out the missed dose. Do not double dose to cover up a missed dose. Record your missed dose and inform your doctor immediately if you missed several doses.


Q Flex may interact with:

  • Cold or anti- allergy medications
  • Sedatives
  • Narcotic pain relievers
  • Muscle relaxant
  • MAO inhibitor drugs (i.e. isocarboxazid, selegiline)
  • Anticonvulsant or anti- epileptic drugs
  • Sleeping pills and
  • Antidepressants.

Some drugs may either lessen the beneficial effects or worsen the side effects of Q Flex. Likewise, Q Flex may make some drugs less efficient or intensify their side effects.

Make sure to inform your doctor about all other drugs you are currently taking or using (prescribed and non-prescribed medications including vitamins, minerals and herbal products) to check for possible drug interaction with Q Flex.

Never alter the doses of other medications while on Q Flex neither stop nor start any medicine without the doctor’s recommendation.

Side Effects:

There are no side effects known aside from a possible allergic reaction in people who have previous or unknown hypersensitivity to the drug.

Watch out for signs of allergic reactions such as:

  • Rash
  • Itching
  • Swelling


Before taking Q Flex tell your health care provider if you have/are:

  • Any allergies to any substance, food or medication, particularly to acetaminophen and phenyltoloxamine (Q Flex)
  • Medical history or a present condition such as:
  • Pregnant, planning to get pregnant or currently breastfeeding a baby (It is not known if Q Flex can harm the unborn child but it can pass through breast milk that may harm the nursing child. The risks and benefits of using this medication during pregnancy must be discussed well with your doctor.)