The following side effects may get better over time as your body gets used to the medication. Let your healthcare provider know immediately if you continue to experience these symptoms or if they worsen over time.
Common Side Effects
- Sleepiness
- Dry mouth
- Blurry vision
- Constipation
- Nausea
- Vomiting
- Diarrhea
Less Common Side Effects
- Nighttime confusion
- Tiredness
- Restlessness
- Headache
- Abnormal muscle movements
- Other changes in vision
- Changes in the heartbeat
- Sudden drop in blood pressure when changing positions
- Hives
- Skin that's sensitive to light (higher risk for sunburn)
Thioridazine serious side effects
Contact your healthcare provider immediately if you experience any of the following.
- Abnormal heart rhythm: feeling like your heart is pounding out of your chest, feeling like you're about to faint, dizziness, chest pain
- Uncontrolled muscle movements: involuntarily sticking out your tongue, puffing out your cheeks, puckering your mouth, lip smacking, chewing, or foot tapping
- Neuroleptic malignant syndrome (NMS): very high fever, sweating, muscle stiffness, confusion, abnormal pulse, fast heartbeat, changes in blood pressure
- Seizures
Source: DailyMed
The following Thioridazine side effects have also been reported
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.
Phenothiazines can sometimes cause serious unwanted effects. Tardive dyskinesia or tardive dystonia (muscle movement disorders) may occur and may not go away after you stop using the medicine. Signs of tardive dyskinesia or tardive dystonia include worm-like movements of the tongue, or other uncontrolled movements of the mouth, tongue, cheeks, jaw, body, arms, or legs. Another possible serious unwanted effect is the neuroleptic malignant syndrome (NMS). Signs and symptoms of NMS include severe muscle stiffness, fever, fast heartbeat, difficult breathing, increased sweating, and loss of bladder control. You and your doctor should discuss the good this medicine will do as well as the risks of taking it.
Stop taking this medicine and get emergency help immediately if any of the following effects occur:
Rare
Symptoms of neuroleptic malignant syndrome
Confusion (severe) or coma
difficult or fast breathing
fast heartbeat
high or low (irregular) blood pressure
increased sweating
loss of bladder control
muscle stiffness (severe)
trembling or shaking
trouble in speaking or swallowing
Check with your doctor immediately if any of the following side effects occur:
More common
Inability to move eyes
increased blinking or spasms of eyelid
lip smacking or puckering
muscle spasms of face, neck, body, arms, or legs causing unusual postures or unusual expressions on face
puffing of cheeks
rapid or worm-like movements of tongue
sticking out of tongue
tic-like or twitching movements
trouble in breathing, speaking, or swallowing
uncontrolled chewing movements
uncontrolled movements of arms or legs
uncontrolled twisting movements of neck, trunk, arms, or leg
Rare
Irregular or slow heart rate
recurrent fainting
Check with your doctor as soon as possible if any of the following side effects occur:
More common
Blurred vision, change in color vision, or difficulty in seeing at night
fainting
loss of balance control
mask-like face
restlessness or need to keep moving
shuffling walk
stiffness of arms or legs
trembling and shaking of hands and fingers
Less common
Difficulty in urinating
skin rash
sunburn (severe)
Rare
Abdominal or stomach pains
aching muscles and joints
agitation, bizarre dreams, excitement, or trouble in sleeping
bleeding or bruising (unusual
clumsiness
confusion (mild)
constipation (severe)
convulsions (seizures)
dark urine
fever and chills
headaches
hot, dry skin or lack of sweating
itchy skin (severe)
muscle weakness
pain in joints
prolonged, painful, inappropriate erection of the penis
redness of hands
shivering
skin discoloration (tan or blue-gray)
sore throat and fever
sores in mouth
unusual bleeding or bruising
unusual tiredness or weakness
yellow eyes or skin
Phenothiazines may cause your urine to be dark. In most cases, this is not a sign of a serious problem. However, if your urine does become dark, discuss it with your doctor.
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
Changes in menstrual period
decreased sexual ability
increased sensitivity of eyes to light
rough or “fuzzy” tongue
secretion of milk (unusual)
swelling or pain in breasts
watering of mouth
weight gain (unusual)
After you stop using this medicine, your body may need time to adjust. The length of time this takes depends on the amount of medicine you were using and how long you used it. During this time, check with your doctor if you notice dizziness, nausea and vomiting, stomach pain, trembling of the fingers and hands, or any of the following signs of tardive dyskinesia or tardive dystonia:
Inability to move eyes
lip smacking or puckering
muscle spasms of face, neck, body, arms, or legs, causing unusual body positions or unusual expressions on face
puffing of cheeks
rapid or worm-like movements of tongue
sticking out of tongue
tic-like or twitching movements
trouble in breathing, speaking, or swallowing
uncontrolled chewing movements
uncontrolled twisting or other movements of neck, trunk, arms, or legs
Although not all of the side effects listed above have been reported for all of the phenothiazines, they have been reported for at least one of them. However, since all of the phenothiazines are very similar, any of the above side effects may occur with any of these medicines.
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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