cyproheptadine (Periactin)

Introduction

Tradename: Periactin.

Indications

• allergies, colds, urticaria, rhinorrhea, sneezing, nasal congestion, allergic conjunctivitis
• pruritus
• Cushing's syndrome secondary to pituitary disorders
• male & female anorgasmy
• appetite stimulation in patients with anorexia nervosa
• serotonin syndrome

Contraindications

• narrow-angle glaucoma
• bladder neck obstruction
• stenosing peptic ulcer
• obstruction of the GI tract
• concurrent use of MAO inhibitors
• newborns

pregnancy category = b

safety in lactation = -

Dosage

• adults:
  • 12-16 mg PO QD divided every 8 hours
  • max: 16 mg/day
• children 7-14 years:
  • 4 mg PO every 8-14 hours
  • max: 16 mg/day
• children 2-6 years
  • 2 mg PO every 8-14 hours
  • max: 12 mg/day
• allergies, colds, urticaria: 4 mg PO TID
• Cushing's syndrome secondary to pituitary disorders
  • start 8 mg PO QD
  • gradually increase to 24 mg QD
• male & female anorgasmy
  • 4 to 16 mg 60 minutes prior to sexual activity
• appetite stimulation in patients with anorexia nervosa
  • start 4 mg PO BID/TID
  • gradually increase to 8 mg QID

Tabs: 4 mg.

Syrup: 2 mg/5 mL

Pharmacokinetics

• well absorbed after oral administration
• peak plasma levels occur 6-9 hours after administration
• 70% excreted in the feces

elimination via liver

elimination via kidney

Adverse effects

• common (> 10%)
  • slight to moderate drowsiness
  • thickening of bronchial secretions
• less common (1-10%)
  • headache, fatigue, increased appetite, weight gain, nervousness, dizziness, nausea, diarrhea, abdominal pain, dry mouth, pharyngitis, arthralgia
• uncommon (< 1%)
  • angioedema, bronchospasm, depression, edema, epistaxis, hepatitis, myalgia, palpitations, paresthesia, photosensitivity, rash, tachycardia, hemolytic anemia, leukopenia, thrombocytopenia, sedation, CNS stimulation, seizures, allergic reactions
• anticholinergic effects

• drug adverse effects of H1 receptor antagonists
• drug adverse effects of psychotropic agents
• drug adverse effects of sedatives

Drug interactions

• additive effects with other CNS depressants
• MAO inhibitors increase anticholinergic effects

Mechanism of action

• histamine H1 receptor antagonist
• serotonin receptor antagonist
• some calcium channel blocking activity

More general terms

• H1 receptor antagonist (antihistamine)
• sedative/hypnotic (tranquilizer)

Database

• PubChem: http://pubchem.ncbi.nlm.nih.gov/summary/summary.cgi?cid=2913
• PubChem: http://pubchem.ncbi.nlm.nih.gov/summary/summary.cgi?cid=13770
• PubChem: http://pubchem.ncbi.nlm.nih.gov/summary/summary.cgi?cid=168896
• PubChem: http://pubchem.ncbi.nlm.nih.gov/summary/summary.cgi?cid=167241