Side effects of Phenergan

Side effects requiring immediate medical attention

In addition to the necessary effects, promethazine (the active ingredient in Phenergan) may cause some unwanted effects. Although not all of these side effects may occur, if they do, they may require medical attention.

Stop taking Promethazine and seek immediate emergency treatment if any of the following effects occur:

Rarely

Symptoms of malignant neuroleptic syndrome; two or more symptoms occur simultaneously; most of these effects do not require immediate medical attention if they occur separately.

• convulsions (seizures)
• difficult or unusually rapid breathing
• a fast heartbeat or irregular pulse
• fever
• high or low (irregular) blood pressure
• excessive sweating
• loss of bladder control
• severe muscle stiffness
• unusually pale skin
• unusual fatigue or weakness

Consult your doctor immediately if any of the following side effects occur while taking Promethazine.

Frequency unknown

• stomach or abdominal pain
• black, tarry stools
• bleeding gums
• blood in your urine or feces
• bloody nose
• blurred vision
• pain or discomfort in the chest
• chills
• clay-colored stools
• confusion about time, place, or person
• cough or hoarseness
• dark urine
• decreased awareness or responsiveness
• difficulty or difficulty breathing
• double vision
• a fast, rapid, or irregular heartbeat or pulse
• fever with or without chills
• fixed position of the eye
• headache
• heavier menstrual periods
• fever
• holding false beliefs that cannot be changed by fact
• hyperexcitability
• high or low blood pressure
• excessive sweating
• irregular, rapid or slow, or shallow breathing
• itching
• large, beehive-like swelling on the face, eyelids, lips, tongue, throat, hands, feet, legs, or genitals
• dizziness, lightheadedness, or fainting
• loss of appetite
• loss of bladder control
• low back or side pain
• mimicry of speech or movements
• mutism
• nasal congestion
• nausea
• negativity
• nightmares
• noisy breathing
• shortness of breath
• painful or difficult urination
• pale or blue lips, nails, or skin
• peculiar postures or movements, mannerisms, or grimaces
• pitting red spots on the skin
• double vision
• seeing, hearing or feeling things that are not there
• cramps
• severe muscle stiffness
• extreme sleepiness
• shortness of breath
• skin rash
• slow or irregular heartbeat
• sore throat
• sores, ulcers, or white patches on the lips or mouth
• bulging tongue
• swollen glands
• chest tightness
• trembling
• uncontrollable twisting movements of the neck
• bad breath
• unusual bleeding or bruising
• unusual agitation, nervousness, or restlessness
• unusual fatigue or weakness
• vomiting blood
• shortness of breath
• yellow eyes or skin

Symptoms of overdose

• disappointment
• dizziness, weakness, or dizziness when suddenly standing up from a lying or sitting position
• dry mouth
• excessive muscle tone
• feeling of warmth
• feeling of sadness or emptiness
• irritability
• loss of appetite
• loss of interest or pleasure
• muscle tension or tightness
• overactive reflexes
• pupils of the eyes large, unmoving, and unresponsive to light
• redness of the face, neck, arms, and sometimes the upper chest
• trembling and unsteady gait
• sudden death
• trouble concentrating
• trouble sleeping
• unconsciousness
• unsteadiness, tremors or other problems with muscular control or coordination
• unusual paleness

Side effects that do not require immediate medical attention

Some Promethazine side effects may occur that do not usually require medical attention. These side effects may go away during treatment as your body gets used to the medicine. Your doctor can also tell you about ways to prevent or reduce some of these side effects.

Consult your doctor if any of the following side effects continue or bother you, or if you have any questions about them:

Frequency unknown

• blistering, crusting, irritation, itching, or redness of the skin
• persistent ringing, buzzing, or other unexplained tinnitus
• cracked, dry, flaky skin
• dizziness
• sleepiness
• agitation
• false or unusual sense of well-being
• hearing loss
• hives or welts
• hypersensitivity of the skin to sunlight
• lack of coordination
• loss of strength or energy
• muscle pain or weakness
• redness or other discoloration of the skin
• relaxed and quiet
• sunburn
• swelling
• can’t sleep
• vomiting