Side Effects

Drug information provided by: Merative, Micromedex®

Along with its needed effects, a medicine may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.

Although serious side effects occur rarely when this medicine is taken as recommended, they may be more likely to occur if: too much medicine is taken, it is taken in large doses, or it is taken for a long period of time.

Get emergency help immediately if any of the following symptoms of overdose occur:

For promethazine only

  1. Muscle spasms (especially of neck and back)
  2. restlessness
  3. shuffling walk
  4. tic-like (jerky) movements of head and face
  5. trembling and shaking of hands

Check with your doctor as soon as possible if any of the following side effects occur:


  1. Back, leg or stomach pain
  2. black, sticky stools
  3. bleeding gums
  4. blood, cloudy or dark urine, or sudden decrease in amount of urine
  5. blood pressure increased
  6. blurred vision
  7. chest pain
  8. confusion
  9. diarrhea
  10. dizziness
  11. faintness, or lightheadedness when getting up from a lying or sitting position
  12. fever or chills
  13. light-colored stools
  14. mood or mental changes
  15. nosebleeds
  16. sore throat and fever
  17. skin rash or hives
  18. stillbirth
  19. swollen mouth, throat, face, fingers, feet, glands or lower legs
  20. sweating suddenly
  21. tightness in chest
  22. troubled breathing
  23. twitching, twisting, or uncontrolled repetitive movements of face
  24. unusual bleeding or bruising
  25. unusual tiredness or weakness
  26. vomiting of blood
  27. weight gain suddenly
  28. yellow or pale eyes or skin

Some side effects may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects. Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:

More common

  1. Drowsiness
  2. thickening of the bronchial secretions

Less common

  1. Blurred vision
  2. confusion
  3. difficult or painful urination
  4. dizziness
  5. dryness of mouth, nose, or throat
  6. headache
  7. loss of appetite
  8. nightmares
  9. pounding heartbeat
  10. ringing or buzzing in ears
  11. skin rash
  12. stomach upset or pain (more common with pyrilamine)
  13. unusual excitement, nervousness, restlessness, or irritability
  14. unusual sleepiness, weakness or drowsiness, extreme tiredness

Other side effects not listed may also occur in some patients. If you notice any other effects, check with your healthcare professional.

Call your doctor for medical advice about side effects. You may report side effects to the FDA at 1-800-FDA-1088.

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