Salagen (pilocarpine) is a cholinergic drug used to treat dry mouth caused by Sjogren's syndrome, and radiation to the neck and head, and eye drops are used to treat glaucoma.

Acetylcholine serves as a messenger between nerve cells and between nerve cells and the organs they control. Acetylcholine is responsible for causing the salivary glands to make saliva and the lacrimal glands to make tears to lubricate the eyes.

In addition to its effects on the salivary and lacrimal glands, acetylcholine reduces the production of fluid within the eye.

Common side effects of Salagen include

• excessive sweating,
• chills,
• dizziness,
• excessive tearing,
• flushing,
• voice changes,
• stuffy nose,
• tremor,
• nervousness,
• increased need to urinate,
• visual disturbances,
• diarrhea,
• difficulty swallowing,
• abdominal pain,
• nausea,
• vomiting, and
• high or low blood pressure.

Serious side effects of Salagen include

• shortness of breath,
• slow or increased heart rate,
• severe headache,
• pounding in your neck or ears,
• confusion,
• tremors, and
•  lightheadedness.

Drug interactions of Salagen include medications that have anticholinergic effects since they will counter Salagen's cholinergic effects, such as

• Lomotil,
• some antihistamines,
• some phenothiazines,
• some antidepressants,
• clozapine,
• cyclobenzaprine, and
• disopyramide.

The safety of oral Salagen during pregnancy has not been evaluated. The physician and patient need to weigh the benefits and the unknown risk to the fetus before using Salagen during pregnancy.

It is unknown if Salagen is secreted in human breast milk in amounts large enough to affect the nursing infant. Consult your doctor before breastfeeding. 

Excessive sweating (diaphoresis) is a frequent side effect of pilocarpine. Other side effects include:

• chills,
• dizziness,
• excessive tearing,
• flushing,
• voice change,
• stuffy nose,
• tremor,
• nervousness,
• increased need to urinate,
• visual disturbances,
• diarrhea,
• difficulty swallowing,
• abdominal pain,
• nausea,
• vomiting,
• slow or increased heart rate,
• and high or low blood pressure.

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 Salagen Tablets were a consequence of the expected pharmacologic effects of pilocarpine.

In addition, the following adverse events ( ≥3% incidence) were reported at dosages of 15-30 mg/day in the controlled clinical trials:

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, parethesias, 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 an 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% Asian, 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 of 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 Salagen Tablets:

In addition, the following adverse events ( ≥3% incidence) were reported at dosages of 20 mg/day in the controlled clinical trials:

The following events were reported in Sjogren's patients at incidences of 1% to 2% at dosing of 20 mg/day:

• accidental injury,
• allergic reaction,
• back pain,
• blurred vision,
• constipation,
• increased cough,
• edema,
• epistaxis,
• face edema,
• fever,
• flatulence,
• glossitis,
• lab test abnormalities,
• including chemistry,
• hematology and urinalysis,
• myalgia,
• palpitation,
• pruritus,
• somnolence,
• stomatitis,
• tachycardia,
• tinnitus,
• urinary incontinence,
• urinary tract infection, and
• vaginitis.

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, parethesias, 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.

• Pilocarpine should be administered with caution to patients taking beta-adrenergic antagonists because of the possibility of conduction disturbances.
• Drugs with parasympathomimetic effects administered concurrently with pilocarpine would be expected to result in additive pharmacologic effects.
• Pilocarpine might antagonize the anticholinergic effects of drugs used concomitantly.
• These effects should be considered when anticholinergic properties may be contributing to the therapeutic effect of concomitant medication (e.g., atropine, inhaled ipratropium).

While no formal drug interaction studies have been performed, the following concomitant drugs were used in at least 10% of patients in either or both Sjogren's efficacy studies:

• acetylsalicylic acid,
• artificial tears,
• calcium,
• conjugated estrogens,
• hydroxychloroquine sulfate,
• ibuprofen,
• levothyroxine sodium,
• medroxyprog-esterone acetate,
• methotrexate,
• multivitamins,
• naproxen,
• omeprazole,
• paracetamol, and
• prednisone.