Driptane: composition and presentation
Driptane comes as tablets, each containing 5 mg of oxybutynin hydrochloride. There is only one strength, but half a tablet — 2.5 mg — is in constant use: treatment begins with it in older people and in children from the age of five. The formulation contains lactose, so it does not suit people with the rare hereditary galactose intolerance, Lapp lactase deficiency or glucose-galactose malabsorption, and that is worth checking in advance, because the medicine is taken for a long time and several times a day.
The easiest way to understand this medicine is through a single observation: almost everything written about it — the benefit, the warnings and the side effects — is one and the same mechanism showing itself in different organs. The bladder needs acetylcholine blocked; the salivary glands, the bowel, the eye and the sweat glands get it thrown in.
How Driptane works
Oxybutynin has two complementary actions. The first is a direct spasmolytic effect on the smooth muscle of the detrusor, the muscle that expels urine. The second is anticholinergic: the medicine suppresses the action of acetylcholine on the muscarinic receptors of smooth muscle. Both lead to the same result — relaxation of the detrusor.
What this gives in bladder instability is described concretely: the volume of the bladder increases and the number of spontaneous detrusor contractions falls. In practice that means more urine gathers before the urge comes, and the urge itself arrives less often and less abruptly. The other side of it is this: muscarinic receptors are not only in the bladder, and the medicine cannot choose where to work. It also matters that the action is symptomatic: oxybutynin removes the manifestations of detrusor overactivity but does not remove its cause, so the symptoms return once it is stopped.
Indications
In adults the indication is worded narrowly: relief of the symptoms of bladder instability with disturbed voiding in patients with a neurogenic bladder, in detrusor hyperreflexia. Three manifestations are meant: urgency, urinary incontinence and difficulty in voiding. A neurogenic bladder means that the nervous control of voiding itself is disturbed, and detrusor hyperreflexia that the muscle contracts on its own without waiting to be filled.
For children of five and over and for adolescents there are two indications. The first is incontinence, sudden urgency and frequent voiding in bladder instability caused by idiopathic overactive bladder or by a neurogenic bladder, that is, by excessive detrusor activity. The second is involuntary night-time voiding linked to that same excessive activity, and only in combination with non-drug therapy and only where other methods of treatment have failed. The proviso about "other methods" matters here: the medicine is not the first step in childhood bedwetting but the last.
Method of use and dosage
Adults are usually given 5 mg, that is one tablet, two or three times a day. The dose may be raised to a maximum of 5 mg four times a day if the clinical result calls for it and the patient tolerates the medicine well. In older people the half-life is prolonged, so for them, particularly if frail and of slight build, 2.5 mg — half a tablet — twice a day is usually enough; with good tolerance the dose is raised to 5 mg twice a day.
The schedule of two to four doses a day follows from the short action of a single dose: the medicine does not hold its effect round the clock, so the doses are spread through the day. In every case the dose is set by two guides at once — the result achieved and tolerability — and the second limits the first more often than the other way round. In children from five with neurogenic bladder instability, treatment starts at 2.5 mg twice a day and, where needed and well tolerated, rises to 5 mg two or three times a day. In bedwetting the schedule is the same but with one important correction: the last dose of the day is given before bedtime, otherwise the evening dose loses its point. In children under five the medicine is not recommended: safety in that age group has not been established.
Contraindications
The bans in this section fall into two groups, and both follow from the mechanism. The first covers situations where relaxing smooth muscle is dangerous in itself: narrowing of the bladder outlet where urinary retention may occur; gastrointestinal obstruction, intestinal atony or paralytic ileus; toxic dilation of the colon; severe ulcerative colitis. The bowel is already failing to contract, and the medicine suppresses peristalsis further still.
The second group is the eye and the muscles. Narrow-angle glaucoma, or a shallow anterior chamber, is ruled out because an anticholinergic dilates the pupil and can close an already narrow drainage angle. Myasthenia, because in it the transmission of the signal from nerve to muscle is already disturbed at precisely the level of acetylcholine. The list closes with the standard entry: hypersensitivity to the active substance or to any excipient.
Special warnings and precautions
Caution is needed in frail older people and in children, who are more sensitive to the medicine, as well as in patients with autonomic neuropathy — those with Parkinson's disease, for instance — with severe functional disorders of the digestive tract, with impaired liver or kidney function and with disorders of the cerebral circulation. In older people anticholinergics are used with an eye to the risk of cognitive impairment. An effect of oxybutynin on the central nervous system has been recorded — hallucinations, agitation, confusion, drowsiness; the patient's state should be monitored especially in the first months of treatment and after a dose increase, and if such signs appear, reducing the dose or stopping treatment is to be considered.
| Organ | What the medicine does and what to do about it |
| Mouth | reduces the flow of saliva, and dry mouth leads to caries, periodontal disease and fungal infection; on long treatment regular dental check-ups are advised |
| Eye | can bring on narrow-angle glaucoma; a sudden loss of visual acuity or eye pain calls for immediate contact with a doctor |
| Bowel | peristalsis slows and the contents linger longer on the way down; where the oesophagus is already suffering — hiatus hernia, reflux, bisphosphonate treatment — that adds a risk of inflammation, and the medicine is used with care |
| Sweat glands | reduces sweating, so in hot weather heatstroke becomes possible |
| Heart and vessels | the features of tachycardia, arrhythmia, coronary heart disease, arterial hypertension, congestive heart failure and hyperthyroidism may worsen |
| Prostate | the symptoms of its enlargement may intensify, since the outflow of urine is already impeded |
| Porphyrin metabolism | oxybutynin is regarded as dangerous in porphyria: in animals and in vitro it showed a porphyrinogenic effect |
In children under five the medicine is not recommended. The data supporting its use in monosymptomatic bedwetting — that is, bedwetting unconnected with detrusor overactivity — are limited. In children of five and over caution follows from a possible heightened sensitivity, especially to adverse effects on the nervous system and to psychiatric symptoms. It is noted separately that the medicine may cause drowsiness and blurred vision, so driving, operating machinery and hazardous work call for care.
Interactions with other medicines
The main rule is simple: anticholinergic effects add up. Caution is needed when any agent with an anticholinergic effect is taken at the same time, and the list of those is wider than it seems. It includes amantadine and other anticholinergics used in Parkinson's disease, such as biperiden and levodopa; antihistamines; antipsychotics — phenothiazine derivatives, butyrophenones, clozapine; quinidine; digitalis preparations; tricyclic antidepressants; atropine and the spasmolytics derived from it, and dipyridamole as well.
The second kind of interaction involves metabolism and bowel motility. Oxybutynin is metabolised by the CYP3A4 isoenzyme of cytochrome P450, so inhibitors of that enzyme — itraconazole, for example — slow its metabolism and strengthen its effect. By slowing peristalsis the medicine can affect how far other medicines are absorbed, it weakens the action of prokinetic agents, and taken together with cholinesterase inhibitors it reduces their effectiveness. The patient is also warned about alcohol: it deepens the drowsiness caused by anticholinergic substances.
Pregnancy and breastfeeding
There are no adequate data on the safety of oxybutynin in pregnancy. Animal studies showed harm to reproduction, but at doses toxic to the mothers themselves, and the potential risk in humans remains unknown. The wording of the description is cautious: in pregnancy the medicine should not be used unless it is absolutely necessary.
During breastfeeding oxybutynin passes into milk in small amounts, and for that reason nursing women should not take it. Adequate human data are lacking; animal studies showed no harmful effect on the fertility of females or males. A woman planning a pregnancy should discuss it with her doctor in advance: an overactive bladder is treated for years, and the question will almost certainly arise.
Adverse reactions
Very often there is constipation, nausea, dryness of the mouth, dry skin, dizziness, headache and drowsiness. Common effects are diarrhoea and vomiting, states of confusion, dryness of the eye, urinary retention and flushing of the face. Uncommonly there is abdominal discomfort, anorexia, reduced appetite and difficulty swallowing. That list alone shows these are not scattered reactions but one and the same blockade of muscarinic receptors spread across the organs: in one place it reduces secretion, in another it holds back muscle contraction.
With unknown frequency a wider range is described. On the mental side: agitation, restlessness, hallucinations, nightmares, delusions, cognitive impairment in older people, features of depression, disorientation and delirium, along with dependence in patients with a history of abusing medicines or other substances. On the nervous system: cognitive disturbance and seizures. In the eye: closed-angle glaucoma, dilation of the pupil, raised intraocular pressure and blurred vision. In the digestive tract: gastro-oesophageal reflux and pseudo-obstruction in at-risk patients, meaning older ones or those with constipation who are taking other medicines that slow bowel motility. Also recorded are tachycardia and disturbances of heart rhythm, heatstroke, urinary tract infections and voiding disorders, angioedema, rash, hives, reduced sweating, light sensitivity and hypersensitivity reactions.
Overdose
Overdose shows itself as an intensification of the usual adverse effects: from the nervous system, anything from restlessness and agitation to psychotic behaviour; from the circulation, facial flushing, a fall in blood pressure and circulatory failure; beyond that, respiratory failure, paralysis and coma are possible.
Treatment is mainly symptomatic and is carried out in hospital. The description lists specific steps: immediate gastric lavage; slow intravenous infusion of physostigmine — 0.5 to 2.0 mg in adults, repeated if necessary up to a total of 5 mg, and 30 µg per kilogram of body weight in children up to a total of 2 mg; where anticholinergic symptoms threaten life, neostigmine may be used instead in the doses recommended by its manufacturer. For marked restlessness or agitation 10 mg of diazepam is given intravenously, for tachycardia propranolol; urinary retention is dealt with by catheterisation, and if paralysis of the respiratory muscles advances the patient is put on a ventilator.
How to get a Driptane prescription online
Driptane is dispensed on prescription, and at e-zdrowie.com it can be arranged remotely. You fill in a medical questionnaire, the doctor reviews the answers and, if the medicine is suitable, issues an electronic prescription: the code arrives by message, and any Polish pharmacy will dispense the tablets against it. The format suits the continuation of treatment already settled on: an overactive bladder is a long-standing condition, and once the dose is set it usually stays unchanged for months.
In the questionnaire describe how the complaints show themselves: how often you pass urine by day and by night, sudden urges, episodes of incontinence, difficulty starting to void. State who first prescribed the medicine and when, and what dose you are on. Be sure to report glaucoma, myasthenia, constipation and other bowel diseases, an enlarged prostate, disease of the heart, liver and kidneys, Parkinson's disease, pregnancy or breastfeeding, and list the medicines you take — antidepressants, antipsychotics, antihistamines and antiparkinsonian agents above all. Sudden eye pain or loss of visual acuity during treatment is a reason to see a doctor at once, not to wait for the next prescription.
