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.

Check with your doctor or nurse immediately if any of the following side effects occur:

More common

  1. Excessive muscle tone
  2. inability to move the eyes
  3. increase in body movements
  4. increased blinking or spasms of the eyelid
  5. muscle stiffness, tension, or tightness
  6. sleepiness or unusual drowsiness
  7. sticking out of the tongue
  8. tremor
  9. trouble with breathing, speaking, or swallowing
  10. uncontrolled twisting movements of the neck, trunk, arms, or legs
  11. unusual facial expressions
Haloperidol® Decanoate
  1. Difficulty swallowing
  2. fixed position of the eye
  3. loss of balance control
  4. mask-like face
  5. shuffling walk
  6. slowed movements
  7. slurred speech
  8. stiffness of the arms and legs
  9. tic-like or jerky movements of the head, face, mouth, and neck
  10. trembling and shaking of the fingers and hands

Less common

  1. Slow movement and reflexes
Haloperidol® Decanoate
  1. Absence of or decrease in body movement
  2. inability to sit still
  3. need to keep moving
  4. restlessness

Rare (both)

  1. Blurred vision
  2. confusion
  3. difficulty opening the mouth
  4. dizziness
  5. dizziness, faintness, or lightheadedness when getting up suddenly from a lying or sitting position
  6. fainting
  7. fast, pounding, or irregular heartbeat or pulse
  8. high fever
  9. high or low blood pressure
  10. increased sweating
  11. lightheadedness
  12. lockjaw
  13. loss of bladder control
  14. muscle spasm, especially of the neck and back
  15. muscle twitching
  16. seizures
  17. severe muscle stiffness
  18. uncontrolled eye movements
  19. unusual tiredness or weakness
  20. unusually pale skin

Incidence not known (both)

  1. Anxiety
  2. black, tarry stools
  3. bleeding, blistering, burning, coldness, discoloration of the skin, feeling of pressure, hives, infection, inflammation, itching, lumps, numbness, pain, rash, redness, scarring, soreness, stinging, swelling, tenderness, tingling, or warmth at the injection site
  4. chest pain or tightness
  5. chills
  6. clay-colored stools
  7. cold sweats
  8. continuing nausea or vomiting
  9. cool, pale skin
  10. cough
  11. dark urine
  12. decrease in the frequency of urination
  13. deep or fast breathing with dizziness
  14. depression
  15. difficulty in passing urine (dribbling)
  16. drooling
  17. dry mouth
  18. eye pain
  19. false or unusual sense of well-being
  20. fever with or without chills
  21. flushed, dry skin
  22. fruit-like breath odor
  23. general feeling of illness, tiredness, or weakness
  24. headache
  25. hoarseness
  26. hot, dry skin
  27. increase in the frequency of seizures
  28. increased hunger
  29. increased thirst
  30. increased urination
  31. irregular heartbeat, recurrent
  32. irritability
  33. itching, skin rash
  34. lack of sweating
  35. large, hive-like swelling on the face, eyelids, lips, tongue, throat, hands, legs, feet, or genitals
  36. lip smacking or puckering
  37. loss of appetite
  38. loss of consciousness
  39. lower back or side pain
  40. muscle weakness
  41. muscle pain or cramps
  42. muscle trembling or jerking
  43. nausea
  44. nervousness
  45. nightmares
  46. noisy breathing
  47. numbness of the feet, hands, and around the mouth
  48. painful or difficult urination
  49. pale skin
  50. pounding in the ears
  51. puffing of the cheeks
  52. rapid or worm-like movements of the tongue
  53. shakiness
  54. shuffling walk
  55. sore throat
  56. sores, ulcers, or white spots on the lips or in the mouth
  57. stomach pain
  58. swelling of the face, ankles, or hands
  59. swollen glands
  60. total body jerking
  61. trouble breathing
  62. trouble with sleeping
  63. twisting movements of the body
  64. uncontrolled chewing movements
  65. unexplained weight loss
  66. unpleasant breath odor
  67. unusual bleeding or bruising
  68. unusual dullness, tiredness, weakness, or feeling of sluggishness
  69. vomiting
  70. vomiting of blood
  71. weakness of the arms and legs
  72. yellow 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:

Less common

  1. Constipation
  2. increased watering of the mouth

Rare (both)

  1. Absent, missed, or irregular menstrual periods
  2. acne, pimples
  3. breast discomfort
  4. cramps
  5. decreased interest in sexual intercourse
  6. heavy bleeding
  7. inability to have or keep an erection
  8. increased weight
  9. loss in sexual ability, desire, drive, or performance
  10. medium to heavy, irregular vaginal bleeding between regular monthly periods, which may require the use of a pad or a tampon
  11. stopping of menstrual bleeding
  12. swelling of the breasts or unusual milk production

Incidence not known (both)

  1. Belching
  2. blindness
  3. changes in vision
  4. decreased vision
  5. difficulty having a bowel movement
  6. disturbed color perception
  7. double vision
  8. drowsiness
  9. feeling of constant movement of self or surroundings
  10. fullness or swelling of the breasts
  11. halos around lights
  12. heartburn
  13. increased in sexual ability, desire, drive, or performance
  14. increased interest in sexual intercourse
  15. increased sensitivity of the skin to sunlight
  16. indigestion
  17. loss of hair
  18. night blindness
  19. overbright appearance of lights
  20. pain or tenderness of the breasts
  21. painful or prolonged erection of the penis
  22. redness or other discoloration of the skin
  23. sensation of spinning
  24. severe sunburn
  25. stomach discomfort or upset
  26. tunnel vision
  27. weight loss

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.