WHAT IS THIS MEDICINE AND WHAT IS IT USED FOR?
Salagen contains pilocarpine hydrochloride, a medicine that works by
stimulating muscarinic receptors — the same receptors that the body's natural
chemical messenger (acetylcholine) uses to activate secretion by glands
throughout the body.
By stimulating these receptors, pilocarpine triggers the salivary glands
to produce more saliva and the lacrimal glands to produce more tears.
It is used for: xerostomia (dry mouth) following head and neck
radiotherapy — radiation damage to the salivary glands causes them to produce
little or no saliva, making swallowing, speaking, and maintaining oral health
very difficult; and symptoms of dry mouth and dry eyes in Sjögren's syndrome —
an autoimmune condition in which the immune system attacks moisture-producing
glands.
Pilocarpine does not repair radiation-damaged glands but stimulates
whatever functional tissue remains.
3. HOW TO TAKE THIS MEDICINE
For dry mouth: 5mg three or four times daily, taken with or without food.
The dose may be adjusted within the range of 5mg to 30mg per day depending on
response and tolerability. Start at the lower dose (5mg three times daily) and
increase gradually if needed and tolerated.
For Sjögren's syndrome: 5mg four times daily. Maximum recommended daily
dose is 30mg. Do not stop suddenly — taper if discontinuing long-term
treatment.
Pilocarpine's effects typically begin within 20 to 60 minutes of taking a
tablet and last for 3 to 5 hours. The most common and expected side effect is
sweating — sometimes profuse — which is a sign the medicine is working (it
stimulates sweat glands as well as salivary and lacrimal glands). Taking the
evening dose a few hours before bedtime rather than immediately before sleeping
can help reduce night sweats.
⚠ PATIENT TIP: Sweating is the most predictable
sign that pilocarpine is active. If sweating is very troublesome, taking the
dose with food can help. Most people find the sweating becomes more manageable
after the first few weeks as the body adjusts. Carry a small bottle of water or
sugar-free chewing gum alongside — the combination of pilocarpine and careful
oral hygiene gives the best dry mouth management.
4. POSSIBLE SIDE EFFECTS
|
How Common? |
Side Effects |
|
Very Common |
Sweating (diaphoresis)
— affects most patients, can be profuse. Nausea. Flushing. Increased
urination (urinary frequency). |
|
Common |
Diarrhoea, dizziness,
headache, visual disturbances (blurring or difficulty accommodating —
particularly in low light), lacrimation (increased tearing — the intended
effect), rhinitis (runny nose), increased saliva (the intended effect) |
|
Serious — Tell Your
Doctor |
Cardiovascular effects
in susceptible patients: slow heart rate (bradycardia), low blood pressure,
arrhythmias. Bronchospasm in patients with asthma or COPD. Acute narrow-angle
glaucoma (in predisposed patients): sudden eye pain, red eye, halos — seek emergency
eye care immediately. Severe dehydration from excessive sweating
(particularly in hot environments). |
5. WHO SHOULD NOT TAKE THIS MEDICINE
Pilocarpine must not be used in patients with uncontrolled asthma or
severe COPD (bronchospasm risk), acute iritis (eye inflammation), narrow-angle
glaucoma, or severe cardiovascular disease. It should not be used when the
stimulation of smooth muscle is undesirable (e.g. patients with intestinal or
urinary obstruction). Use with caution in kidney or liver disease,
cardiovascular disease, COPD, asthma, cholelithiasis (gallstones), Parkinson's
disease, or psychiatric conditions.
⚠ ASTHMA AND COPD: Pilocarpine stimulates airway
smooth muscle and can trigger bronchospasm. Use with caution — or avoid — in
patients with asthma or COPD. If breathlessness or wheezing develops after
starting, stop the medicine and contact your doctor.
⚠ VISUAL DISTURBANCE AND DRIVING: Pilocarpine
can cause blurred vision and difficulty with dark adaptation. Avoid driving at
night or in low-light conditions, particularly at the time of peak drug effect.
Do not drive if vision is significantly blurred.
⚠ DEHYDRATION: Profuse sweating, particularly in
hot weather or with physical activity, can cause dehydration. Drink adequate
fluids, particularly in warm conditions.
6. MEDICINES THAT INTERACT WITH THIS TREATMENT
Other cholinergic medicines (such as neostigmine, pyridostigmine) have
additive cholinergic effects — combined use increases the risk of cholinergic
toxicity (excessive secretions, bradycardia, smooth muscle spasm).
Anticholinergic medicines (such as oxybutynin, tolterodine, atropine,
tricyclic antidepressants) oppose pilocarpine's effects and reduce its
effectiveness. Beta-blockers increase the risk of cardiac conduction
disturbances when combined with pilocarpine. Discuss all medicines with your
doctor or pharmacist.
7. HOW TO STORE THIS MEDICINE
Store below 25°C. Keep in original packaging away from moisture and
light. Keep out of reach of children.
8. PRESCRIPTION REQUIREMENT
|
Field |
Details |
|
Status |
Prescription Only
Medicine (POM) — prescribed by oncologists (post-radiotherapy),
rheumatologists (Sjögren's), or GPs with specialist input |
9. GUIDANCE FOR PATIENTS & CAREGIVERS
Take your tablets as prescribed — typically three or four times daily,
with or without food. Sweating is expected and is a sign the medicine is
working — it usually becomes more manageable after the first few weeks. Drink
plenty of fluids.
Avoid night-time doses immediately before sleeping — timing the last dose
a couple of hours before bed reduces night sweats. Be careful driving at night
or in poor lighting conditions, particularly around the time the medicine is at
its strongest (1 to 2 hours after taking it). If you have asthma and notice
wheezing or breathlessness after starting, stop and contact your doctor.
Maintain good oral hygiene throughout — the saliva produced by pilocarpine
helps protect your teeth.
10. PHARMACIST & PRESCRIBER NOTES
|
Field |
Details |
|
Clinical Dispensing
Notes |
Pilocarpine oral
tablets for dry mouth (post-radiotherapy or Sjögren's). Cholinergic agonist —
sweating (diaphoresis) is almost universal and a sign of pharmacological
activity; counsel proactively. Dose: 5mg TDS or QDS; titrate to response; max
30mg/day. Asthma/COPD: contraindicated in severe/uncontrolled cases;
bronchospasm risk. Cardiovascular caution: bradycardia and arrhythmia risk in
susceptible patients. Narrow-angle glaucoma: contraindicated. Anticholinergic
drug interaction: direct pharmacodynamic antagonism — check for concurrent
oxybutynin, tolterodine, tricyclics, antihistamines. Cholinergic drug
interaction: additive effects with neostigmine, pyridostigmine, donepezil.
Visual disturbance: driving caution, particularly at night or during peak effect.
Dehydration: advise fluid intake, particularly in hot weather. Oral hygiene
counselling: pilocarpine-generated saliva reduces dental caries risk —
complement with good dental care. |
11. FREQUENTLY ASKED QUESTIONS
Q: Why does pilocarpine make me sweat so much?
Pilocarpine stimulates muscarinic receptors throughout the body —
including those in the sweat glands. This is an expected effect of how the
medicine works, not a side effect to be concerned about. It is a sign that the
medicine is active. Most people find the sweating reduces after the first few
weeks as their body adjusts.
Q: Why might my vision be blurred after taking the tablet?
Pilocarpine affects the muscles of the eye that control the pupil size
and focus (accommodation). This can cause blurred vision, difficulty focusing,
and problems seeing in dim light. These effects are most noticeable 1 to 2
hours after each dose. Avoid driving at night or in poor light around these
peak times.
Q: What should I do if I develop wheezing after starting pilocarpine?
Stop the medicine immediately and contact your doctor. Pilocarpine can
trigger bronchospasm (narrowing of the airways) in people with asthma or COPD.
If wheezing is severe, use your reliever inhaler and seek emergency care.