Pilocarpine Hydrochloride

INDICATIONS AND USAGE: Pilocarpine hydrochloride tablets, USP are indicated for 1) the treatment of symptoms of dry mouth from salivary gland hypofunction caused by radiotherapy for cancer of the head and neck; and 2) the treatment of symptoms of dry mouth in patients with Sjogren's syndrome.

DOSAGE AND ADMINISTRATION: Regardless of the indication, the starting dose in patients with moderate hepatic impairment should be 5 mg twice daily, followed by adjustment based on therapeutic response and tolerability. Patients with mild hepatic insufficiency do not require dosage reductions. The use of pilocarpine in patients with severe hepatic insufficiency is not recommended. If needed, refer to the Hepatic Insufficiency subsection of the Precautions section of this label for definitions of mild, moderate and severe hepatic impairment. Head & Neck Cancer Patients: The recommended initial dose of pilocarpine hydrochloride tablets is 5 mg taken three times a day. Dosage should be titrated according to therapeutic response and tolerability. The usual dosage range is 15-30 mg per day. (Not to exceed 10 mg per dose.) Although early improvement may be realized, at least 12 weeks of uninterrupted therapy with pilocarpine hydrochloride tablets may be necessary to assess whether a beneficial response will be achieved. The incidence of the most common adverse events increases with dose. The lowest dose that is tolerated and effective should be used for maintenance. Sjogren's Syndrome Patients: The recommended dose of pilocarpine hydrochloride tablets is one tablet (5 mg) taken four times a day. Efficacy was established by 6 weeks of use.

ADVERSE REACTIONS: Head & Neck Cancer Patients: In controlled studies, 217 patients received pilocarpine, of whom 68% were men and 32% were women. Race distribution was 91% Caucasian, 8% Black, and 1% of other origin. Mean age was approximately 58 years. The majority of patients were between 50 and 64 years (51%), 33% were 65 years and older and 16% were younger than 50 years of age. The most frequent adverse experiences associated with pilocarpine hydrochloride tablets were a consequence of the expected pharmacologic effects of pilocarpine. Adverse Event Pilocarpine HCl Placebo 10 mg t.i.d. (30 mg/day) 5 mg t.i.d. (15 mg/day) (t.i.d.) n=121 n=141 n=152 Sweating 68% 29% 9% Nausea 15 6 4 Rhinitis 14 5 7 Diarrhea 7 4 5 Chills 15 3 <1 Flushing 13 8 3 Urinary Frequency 12 9 7 Dizziness 12 5 4 Asthenia 12 6 3 In addition, the following adverse events (≥3% incidence) were reported at dosages of 15-30 mg/day in the controlled clinical trials: Adverse Event Pilocarpine HCl Placebo 5-10 mg t.i.d. (15-30 mg/day) (t.i.d.) n=212 n=152 Headache 11% 8% Dyspepsia 7 5 Lacrimation 6 8 Edema 5 4 Abdominal Pain 4 4 Amblyopia 4 2 Vomiting 4 1 Pharyngitis 3 8 Hypertension 3 1 The following events were reported with treated head and neck cancer patients at incidences of 1% to 2% at dosages of 7.5 to 30 mg/day: abnormal vision, conjunctivitis, dysphagia, epistaxis, myalgias, pruritus, rash, sinusitis, tachycardia, taste perversion, tremor, voice alteration. The following events were reported rarely in treated head and neck cancer patients (<1%): Causal relation is unknown. Body as a whole: body odor, hypothermia, mucous membrane abnormality Cardiovascular: bradycardia, ECG abnormality, palpitations, syncope Digestive: anorexia, increased appetite, esophagitis, gastrointestinal disorder, tongue disorder Hematologic: leukopenia, lymphadenopathy Nervous: anxiety, confusion, depression, abnormal dreams, hyperkinesia, hypesthesia, nervousness, paresthesias, speech disorder, twitching Respiratory: increased sputum, stridor, yawning Skin: seborrhea Special senses: deafness, eye pain, glaucoma Urogenital: dysuria, metrorrhagia, urinary impairment In long-term treatment were two patients with underlying cardiovascular disease of whom one experienced a myocardial infarct and another episode of syncope. The association with drug is uncertain. Sjogren's Syndrome Patients: In controlled studies, 376 patients received pilocarpine, of whom 5% were men and 95% were women. Race distribution was 84% Caucasian, 9% Oriental, 3% Black, and 4% of other origin. Mean age was 55 years. The majority of patients were between 40 and 69 years (70%), 16% were 70 years and older and 14% were younger than 40 years of age. Of these patients, 161/629 (89/376 receiving pilocarpine) were over the age of 65 years. The adverse events reported by those over 65 years and those 65 years and younger were comparable except for notable trends for urinary frequency, diarrhea, and dizziness. The incidences of urinary frequency and diarrhea in the elderly were about double those in the non-elderly. The incidence of dizziness was about three times as high in the elderly as in the non-elderly. These adverse experiences were not considered to be serious. In the 2 placebo-controlled studies, the most common adverse events related to drug use were sweating, urinary frequency, chills, and vasodilatation (flushing). The most commonly reported reason for patient discontinuation of treatment was sweating. Expected pharmacologic effects of pilocarpine include the following adverse experiences associated with pilocarpine hydrochloride tablets: Adverse Event Pilocarpine HCl Placebo 5 mg q.i.d. (20 mg/day) (q.i.d.) n=255 n=253 Sweating 40% 7% Urinary Frequency 10 4 Nausea 9 9 Flushing 9 2 Rhinitis 7 8 Diarrhea 6 7 Chills 4 2 Increased Salivation 3 0 Asthenia 2 2 In addition, the following adverse events (≥3% incidence) were reported at dosages of 15-30 mg/day in the controlled clinical trials: Adverse Event Pilocarpine HCl Placebo 5 mg q.i.d. (20 mg/day) (q.i.d.) n=255 n=253 Headache 13% 19% Flu Syndrome 9 9 Dyspepsia 7 7 Dizziness 6 7 Pain 4 2 Sinusitis 4 5 Abdominal Pain 3 4 Vomiting 3 1 Pharyngitis 2 5 Rash 2 3 Infection 2 6 The following events were reported with treated head and neck cancer patients at incidences of 1% to 2% at dosages of 7.5 to 30 mg/day: abnormal vision, conjunctivitis, dysphagia, epistaxis, myalgias, pruritus, rash, sinusitis, tachycardia, taste perversion, tremor, voice alteration. The following events were reported rarely in treated Sjogren's patients (<1%) at dosing of 10-30 mg/day: Causal relation is unknown. Body as a whole: chest pain, cyst, death, moniliasis, neck pain, neck rigidity, photosensitivity reaction Cardiovascular: angina pectoris, arrhythmia, ECG abnormality, hypotension, hypertension, intracranial hemorrhage, migraine, myocardial infarction Digestive: anorexia, bilirubinemia, cholelithiasis, colitis, dry mouth, eructation, gastritis, gastroenteritis, gastrointestinal disorder, gingivitis, hepatitis, abnormal liver function tests, melena, nausea & vomiting, pancreatitis, parotid gland enlargement, salivary gland enlargement, sputum increased, taste loss, tongue disorder, tooth disorder Hematologic: hematuria, lymphadenopathy, abnormal platelets, thrombocythemia, thrombocytopenia, thrombosis, abnormal WBC Metabolic and Nutritional: peripheral edema, hypoglycemia Musculoskeletal: arthralgia, arthritis, bone disorder, spontaneous bone fracture, pathological fracture, myasthenia, tendon disorder, tenosynovitis Nervous: aphasia, confusion, depression, abnormal dreams, emotional lability, hyperkinesia, hypesthesia, insomnia, leg cramps, nervousness, paresthesias, abnormal thinking, tremor Respiratory: bronchitis, dyspnea, hiccup, laryngismus, laryngitis, pneumonia, viral infection, voice alteration Skin: alopecia, contact dermatitis, dry skin, eczema, erythema nodosum, exfoliative dermatitis, herpes simplex, skin ulcer, vesiculobullous rash Special senses: cataract, conjunctivitis, dry eyes, ear disorder, ear pain, eye disorder, eye hemorrhage, glaucoma, lacrimation disorder, retinal disorder, taste perversion, abnormal vision Urogenital: breast pain, dysuria, mastitis, menorrhagia, metrorrhagia, ovarian disorder, pyuria, salpingitis, urethral pain, urinary urgency, vaginal hemorrhage, vaginal moniliasis The following adverse experiences have been reported rarely with ocular pilocarpine: A-V block, agitation, ciliary congestion, confusion, delusion, depression, dermatitis, middle ear disturbance, eyelid twitching, malignant glaucoma, iris cysts, macular hole, shock, and visual hallucination.

Pharmacokinetics: In a multiple-dose pharmacokinetic study in male volunteers following 2 days of 5 or 10 mg of oral pilocarpine hydrochloride tablets given at 8 a.m., noontime, and 6 p.m., the mean elimination half-life was 0.76 hours for the 5 mg dose and 1.35 hours for the 10 mg dose. T max values were 1.25 hours and 0.85 hours. C max values were 15 ng/mL and 41 ng/mL. The AUC trapezoidal values were 33 h(ng/mL) and 108 h(ng/mL), respectively, for the 5 and 10 mg doses following the last 6 hour dose. Pharmacokinetics in elderly male volunteers (n = 11) were comparable to those in younger men. In five healthy elderly female volunteers, the mean C max and AUC were approximately twice that of elderly males and young normal male volunteers. When taken with a high fat meal by 12 healthy male volunteers, there was a decrease in the rate of absorption of pilocarpine from pilocarpine hydrochloride tablets. Mean T max's were 1.47 and 0.87 hours, and mean C max's were 51.8 and 59.2 ng/mL for fed and fasted, respectively. Limited information is available about the metabolism and elimination of pilocarpine in humans. Inactivation of pilocarpine is thought to occur at neuronal synapses and probably in plasma. Pilocarpine and its minimally active or inactive degradation products, including pilocarpic acid, are excreted in the urine. Pilocarpine does not bind to human or rat plasma proteins over a concentration range of 5 to 25,000 ng/mL. The effect of pilocarpine on plasma protein binding of other drugs has not been evaluated. In patients with mild to moderate hepatic impairment (n=12), administration of a single 5 mg dose resulted in a 30% decrease in total plasma clearance and a doubling of exposure (as measured by AUC). Peak plasma levels were also increased by about 30% and half-life was increased to 2.1 hrs. There were no significant differences in the pharmacokinetics of oral pilocarpine in volunteer subjects (n=8) with renal insufficiency (mean creatinine clearances 25.4 mL/min; range 9.8 – 40.8 mL/min) compared to the pharmacokinetics previously observed in normal volunteers.