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Drug Profile

The information on this site is intended to supplement and enhance, not replace, the advice of a physician who is familiar with your medical history. Decisions about your health should always be made ONLY after detailed conversation with your doctor.

Generic drug name: cyproheptadine (si proe HEP ta deen)
Brand name(s): PERIACTIN
GENERIC: available FAMILY: Antihistamines
Find the drug label by searching at DailyMed.

Pregnancy and Breast-feeding Warnings [top]

Pregnancy Warning

Cyproheptadine caused fetal harm in an animal study. Because of the potential for serious adverse effects to the fetus, this drug should not be used by pregnant women.

Breast-feeding Warning

Because of the adverse effects on the brains of nursing infants, cyproheptadine should not be used by nursing women.

Safety Warnings For This Drug [top]

Anticholinergic Effects

Warning: Special Mental and Physical Adverse Effects

Older adults are especially sensitive to the harmful anticholinergic effects of these drugs. Drugs in this family should not be used unless absolutely necessary.

Mental Effects: confusion, delirium, short-term memory problems, disorientation and impaired attention

Physical Effects: dry mouth, constipation, difficulty urinating (especially for a man with an enlarged prostate), blurred vision, decreased sweating with increased body temperature, sexual dysfunction and worsening of glaucoma

Non-Drug Approaches to Allergies

Avoid exposure to things that trigger your allergies or asthma, such as animals, bedding, chemicals, cosmetics, drugs, dust, mold, foods, pollens, or smoke. Wearing a mask reduces inhalation of drugs, pollens, and smoke. Many people with mildly red, itching eyes require no treatment. Cold compresses to the eyes may prove helpful. Using eye drops with vasoconstrictors whitens eyes for a while, but rebound redness can occur. Misuse of vasoconstrictors sets up a vicious cycle.

Facts About This Drug [top]

Cyproheptadine was approved by the FDA in 1961. At one time the drug was heavily promoted as an appetite stimulant for children.[1] Appetite stimulation is not an FDA-approved use for this drug, and it should not be used for this purpose.

Cyproheptadine should not be used to treat a cold. Colds and allergies have different causes, and cyproheptadine is not effective against either the cause of a cold or its symptoms. In fact, the drug can make a cold or cough worse by thickening nasal...

Cyproheptadine was approved by the FDA in 1961. At one time the drug was heavily promoted as an appetite stimulant for children.[1] Appetite stimulation is not an FDA-approved use for this drug, and it should not be used for this purpose.

Cyproheptadine should not be used to treat a cold. Colds and allergies have different causes, and cyproheptadine is not effective against either the cause of a cold or its symptoms. In fact, the drug can make a cold or cough worse by thickening nasal secretions and drying mucous membranes. It also causes drowsiness.

Cyproheptadine can cause harmful adverse effects, most commonly in people over 60. These effects include confusion, dizziness, or fainting; difficult or painful urination; dry mouth, nose, or throat; nightmares; or unusual excitement, nervousness, restlessness, and irritability. If you have any of these while taking cyproheptadine, ask your doctor about changing or discontinuing this drug.

In 2015, a study published in JAMA Internal Medicine showed that strong anticholinergic drugs such as cyproheptadine were associated with an increased risk for dementia in older adults.[2],[3]

Before You Use This Drug [top]

Tell your doctor if you have or have had:

  • allergies to drugs
  • peptic ulcer
  • problems with urination
  • gastrointestinal obstruction
  • glaucoma
  • kidney problems
  • enlarged prostate
  • pregnancy or are breast-feeding

Tell your doctor about any other drugs you take, including aspirin, herbs, vitamins, and other nonprescription products.

When You Use This Drug [top]

  • Do not drink alcohol or use other drugs that can cause drowsiness.
  • Until you know how you react to this drug, do not drive or perform other activities requiring alertness.
  • If you plan to have any surgery, including dental surgery, tell your doctor that you take this drug.
  • Protect yourself from sunburn, using a sunscreen or wearing protective clothing.
  • Use sugarless gum, ice, or saliva substitutes if dry mouth develops.

How to Use This Drug [top]

  • If you miss a dose, take it as soon as you remember, but skip it if it is almost time for the next dose. Do not take double doses.
  • Do not share your medication with others.
  • Take the drug at the same time(s) each day.
  • Take with food, water, or milk to avoid stomach upset.
  • Swallow extended-release forms whole.
  • Do not store in the bathroom. Do not expose to heat, moisture, or strong light. Do not allow liquid form to freeze. Keep out of reach of children.

Interactions with Other Drugs [top]

The following drugs, biologics (e.g., vaccines, therapeutic antibodies), or foods are listed in Evaluations of Drug Interactions 2003 as causing “highly clinically significant” or “clinically significant” interactions when used together with any of the drugs in this section. In some sections with multiple drugs, the interaction may have been reported for one but not all drugs in this section, but we include the interaction because the drugs in this section are similar to one another. We have also included potentially serious interactions listed in the drug’s FDA-approved professional package insert or in published medical journal articles. There may be other drugs, especially those in the families of drugs listed below, that also will react with this drug to cause severe adverse effects. Make sure to tell your doctor and pharmacist the drugs you are taking and tell them if you are taking any of these interacting drugs:

DILANTIN, EFFEXOR, fluoxetine, fluvoxamine, LUVOX, nefazodone, paroxetine, PAXIL, phenytoin, PROZAC, SERZONE, venlafaxine

Adverse Effects [top]

Call your doctor immediately if you experience:

  • sore throat
  • cough
  • difficulty swallowing
  • dizziness
  • hives
  • itching
  • puffiness or swelling of the eyelids or around the eyes, face, lips, or tongue
  • shortness of breath
  • skin rash
  • unusual bleeding or bruising
  • tightness in chest
  • unusual tiredness or weakness
  • wheezing
  • abdominal or stomach pain
  • diarrhea
  • chills
  • clay-colored stools or dark urine
  • fever
  • headache
  • convulsions or seizures
  • burning, prickly, tingling sensations
  • fast or irregular heartbeat
  • tingling

Call your doctor if these symptoms continue:

  • increased appetite or weight gain
  • thickening of mucus
  • blurred vision or any change in vision
  • confusion
  • difficult or painful urination
  • dizziness
  • increased sweating
  • increased appetite or weight gain
  • nightmares
  • loss of appetite
  • ringing or buzzing in ears
  • skin rash
  • stomach upset or pain
  • nausea or vomiting
  • unusually fast heartbeat
  • increased sensitivity to the sun
  • clumsiness or unsteadiness
  • constipation
  • menstrual cycle changes
  • tremor
  • diarrhea
  • fatigue
  • tremor

Signs of overdose:

  • clumsiness or unsteadiness
  • severe dry mouth, nose, or throat
  • flushed or red face
  • shortness of breath
  • trouble breathing
  • fast or irregular heartbeat
  • severe drowsiness
  • seizures
  • hallucinations
  • trouble sleeping
  • faintness or lightheadedness

If you suspect an overdose, call this number to contact your poison control center: (800) 222-1222.

last reviewed February 28, 2021