Flavoxate: Indications, Side Effects, Precautions and Recommendations

It is a drug that is used in various urinary syndromes and as an antispasmodic.

Its therapeutic utility and mechanism of action are unclear. It may have local anesthetic activity and direct relaxant effects on smooth muscle, as well as some activity as a muscarinic antagonist.

Flavoxate is a synthetic parasympatholytic with antimuscarinic, muscle relaxant, and urinary antispasmodic properties.

It binds to and inhibits muscarinic receptors, suppressing the urination reflex and increasing the capacity of the urinary bladder by modifying the center of urination in the brainstem.

Furthermore, this agent has been found to inhibit cyclic AMP formation in the striatal membranes of the brain.

All of this through stimulation of pertussis toxin-sensitive G-protein-coupled receptors that in turn suppress isovolumic urinary bladder contraction.


This drug is used for symptomatic relief of urgency, dysuria, suprapubic pain, nocturia, incontinence, and frequency, as can occur in cystitis , urethritis , prostatitis, and urethrocystitis / urethrotrigonitis.

Flavoxate is a synthetic anticholinergic agent used to treat urinary incontinence and overactive bladder syndrome.

Flavoxate has not been implicated in elevation of liver enzymes or clinically apparent acute liver injury.

Side effects of flavoxate

This medicine has the potential to cause dry mouth, nausea, drowsiness, headache, vomiting, dizziness, nervousness, and blurred vision.

If any of these effects do not go away or get worse, see your doctor or pharmacist as soon as possible.

To reduce dry mouth, you can suck on candy (sugar-free) or ice chips, chew gum (sugar-free), drink water, or use a substitute for saliva.

To avoid constipation , it is necessary to maintain a diet with sufficient levels of fiber, drink plenty of water, and do physical exercise. If you suffer from constipation, contact your pharmacist to suggest a suitable laxative.

It is important to remember and take into account that if your doctor prescribed this drug it was because he is sure that its benefits for you outweigh the risk of side effects.

Side effects are not very common among flavoxate users.

See your doctor as soon as possible if you notice any of these rare but severe side effects:

  • Mental or mood changes (for example, confusion).
  • Pain or discomfort in the eyes.
  • Chest pain
  • Heart with strong and fast beats.
  • Signs of infection (such as fever, prolonged sore throat).
  • Stomach or intestinal obstruction (such as persistent nausea or vomiting, prolonged constipation).
  • Difficulty or pain urinating.

Strong allergic reactions caused by this drug are not common. However, do not hesitate to seek urgent medical help in the event of a severe allergic reaction, including:

  • Acne.
  • Itching or swelling (especially of the face, tongue, and throat).
  • Strong dizziness
  • Difficulty breathing.

It is important to note that these are not all the side effects that can be suffered. If symptoms other than those already mentioned appear, contact your doctor urgently.


You need to talk to your doctor and tell him if you are allergic to this drug or if you suffer from any other allergies, as it may have passive components that can cause allergic reactions and complications.

You should see your doctor to determine if you have stomach or intestinal obstruction, bleeding in the stomach or intestines, bladder blockage. In case of suffering from any of these conditions, it is advisable not to consume the medicine.

It can also be a cause of decreased sweating. In order to lessen the danger of a strong reaction to excess heat, try as much as possible not to overheat in hot climates, saunas, or exercise or other strenuous actions.

Side effects are stronger in older adults, especially dizziness, numbness, constipation, trouble urinating, or confusion.

Consumption when pregnant should only be when strictly necessary. It is not known if flavoxate passes into breast milk. It is recommended to consult your doctor before breastfeeding.


If the person who overdoses shows symptoms such as breathing problems or fainting, call 911 as soon as possible or call a poison control center.

Symptoms may include: slow breathing, hallucinations, seizures, or loss of consciousness.

Notes: It  is extremely important not to share this drug with others.

The Flavoxate prescription only applies to the condition determined by your doctor. Do not use it to treat another condition, unless your doctor tells you otherwise.

Flavoxate helps relieve symptoms of a bladder infection, urinary tract infection (UTI), or prostate infection. However, it is not effective in treating an infection. In that case an antibiotic may be needed.

Missed dose

If you did not remember to take a dose, take it as soon as you remember. If the time for the next dose is close, ignore the missed dose and continue your normal dosing schedule. Avoid doubling the dose to make up for the one you missed.


Avoid contact with children and pets.

Also, do not flush medications down the toilet or pour them down the sink unless instructed to do so. Dispose of the product properly when it expires or when it is no longer useful.

You can discuss with your doctor the best way to dispose of flavoxate.