Cyproheptadine (Periactin) Contraindications and Precautions
- breast-feeding
- neonates
- asthma
- bladder obstruction
- cardiac disease
- children
- chronic obstructive pulmonary disease (COPD)
- closed-angle glaucoma
- contact lenses
- driving or operating machinery
- elderly
- GI obstruction
- hepatic disease
- ileus
- pregnancy
- prostatic hypertrophy
- urinary retention
Cyproheptadine (Periactin) Contraindications and Precautions
Use antihistamines with caution in patients with asthma. The anticholinergic activity of H1-antagonists may result in thickened bronchial secretions in the respiratory tract thereby aggravating an acute asthmatic attack or chronic obstructive pulmonary disease (COPD). Although H1-antagonists should be avoided during an acute asthmatic attack, these anticholinergic effects do not preclude the use of H1-antagonists in all asthmatic or COPD patients, particularly if the above respiratory symptom is not a primary component of the illness. Cyproheptadine exhibits only a moderate amount of anticholinergic activity; although, the use of an H1-antagonist with less anticholinergic activity may be preferable in some instances.
Cyproheptadine is classified as pregnancy category B. H1-antagonists generally are not recommended for use in pregnancy, especially during the third trimester, because of a seizure risk to the fetus. Cyproheptadine should be considered during pregnancy only when the benefits of therapy outweigh the risks to the fetus. In general, H1-antagonists are not recommended for use during breast-feeding because they can induce a paradoxical CNS stimulation in neonates or seizures in premature infants. Inhibition of lactation may also occur. Alternative methods of feeding should be used if cyproheptadine therapy is necessary.
Cyproheptadine should be used with caution in children since a paradoxical CNS stimulation can occur. There have been a number of cases of respiratory depression, sleep apnea, and SIDS in children receiving phenothiazine antihistamines. The mechanism of this reaction is not yet known; therefore, antihistamines should be used with extreme caution in children with a family history of SIDS or sleep apnea. H1-antagonists should not be used in neonates due to the possibility of paradoxical CNS stimulation or seizures.
Although cyproheptadine has only moderate anticholinergic effects, a worsening of symptoms may be seen in patients with bladder obstruction, GI obstruction or ileus, benign prostatic hypertrophy, or urinary retention. These precautions are most significant when using antihistamines from the ethanolamine and phenothiazine groups. The elderly are more susceptible to the anticholinergic effects of drugs since there is a decline in endogenous cholinergic activity that occurs with age.
Cyproheptadine should be used conservatively in patients with closed-angle glaucoma. An increase in intraocular pressure may occur from the anticholinergic actions of the drug, precipitating an acute attack of glaucoma. Elderly patients are more susceptible to the anticholinergic effects of cyproheptadine, including possible precipitation of undiagnosed glaucoma. Other ocular effects resulting from the anticholinergic effects of cyproheptadine include dry eyes or blurred vision. This may be of significance in the elderly and wearers of contact lenses.
Cyproheptadine is extensively metabolized in the liver. The metabolism of cyproheptadine may be reduced in the presence of hepatic impairment. Those with significant hepatic disease receiving cyproheptadine should be monitored for liver function and side effects. Dosage adjustments may be required in these patients.
The quinidine-like local anesthetic and anticholinergic effects of antihistamines are responsible for the adverse cardiac effects which have been observed including tachycardia, ECG changes, hypotension, and arrhythmias. Although these cardiovascular effects are uncommon, H1-antagonists should be used conservatively in patients with cardiac disease.
Cyproheptadine can cause drowsiness. Patients receiving cyproheptadine should be advised to avoid driving or operating machinery until the effects of the drug are known.
[ Last revised: 1/5/2003 6:39:00 PM ]
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