Assessing drug utilization and drug-drug interactions in the management of epilepsy, Alzheimer's, Parkinson's disease and migraine

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Journal of Pharmaceutical Health Services Research, 2023, XX, 1–7
https://doi.org/10.1093/jphsr/rmad034
Advance access publication 1 July 2023
Research Paper
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Received: 24 August 2022 Accepted: 19 May 2023
Assessing drug utilization and drug–drug interactions in
the management of epilepsy, Alzheimer’s, Parkinson’s
disease and migraine
NilaySolanki1 * , IshitaChampaneri1 and VarshaPatel2
1Department of Pharmacology, Ramanbhai Patel College of Pharmacy, Charotar University of Science and Technology, CHARUSAT-Campus,
Changa, India
2Department of Pharmacology, Dr. M.K. Shah Medical College and Research Center, Ahmedabad, India
*Correspondence: Nilay Solanki, Department of Pharmacology, Ramanbhai Patel College of Pharmacy, Charotar University of Science and Technology,
CHARUSAT-Campus, Changa, Gujarat, India. Tel: +09904616473; Email: nivyrx@gmail.com
Abstract
Background: Neurological disorders (ND) affect the structure and function of the central nervous system, including Alzheimer’s and
Parkinson’s diseases, epilepsy, migraine and stroke. ND has major symptoms ranging from mild to severe memory problems and phys-
ical disabilities. The present study investigated central nervous system (CNS) drug utilization trends, drug–drug interaction and morbidity
patterns in ND.
Methods: A prospective study was carried out at a multi-specialty hospital, including neurology outpatient cases, in 2016. A study was ethically
approved by the institutional ethics committee (IEC) for human research, and data were collected from patients’ case records. The prescribing
trend was assessed by World Health Organization (WHO) core prescribing indicators. The International Classification of Diseases (ICD) 10 was
used to assess the morbidity pattern. Drug–drug interactions were analysed by a multidrug interaction checker.
Results: We discovered that 53.57% and 46.42% of the 280 neurology cases were female and male, respectively. Here, we showed that ep-
ilepsy was the most commonly diagnosed (31.07%) condition, followed by migraine (30.35%), Parkinsonism (Pn) (13.21%), Alzheimer’s and
dementia (AD) (10.71%) and myasthenia gravis (7.14%). The most commonly used CNS drugs were sodium valproates. Donepezil, fluoxatin and
levodopa–carbidopa. In this study, 80% of drugs were prescribed with the most common category being antiepileptics; 16.77% and 23.21% of
prescriptions observed potential drug–drug interactions.
Conclusions: The treatment priority for epilepsy was sodium valproate, which had a high prescription rate. For AD, donepezil was given priority,
while in PN, levodopa–carbidopa was prescribed most often. In significant drug–drug interactions (DDI), pharmacodynamic mechanisms were
very common, while in minor DDI, pharmacokinetic mechanisms were observed.
Keywords: epilepsy; Alzheimer’s disease; drug utilization trend; sodium valproate; donepezil; drug interactions
Introduction
Epilepsy, Alzheimer’s disease (AD), dementia, headache, mi-
graine, multiple sclerosis (MS), Parkinson’s disease (PD),
stroke and brain tumours are the most prevalent neurolog-
ical disorders (ND) worldwide, with the major causes
of ND including trauma, starvation and neurohumoral
abnormalities.[1–5] There is a major concern worldwide about
the signicant causes of morbidity and mortality that adversely
affect the quality of life amongst all age groups of patients.[6]
Epilepsy is the most common neurological disorder amongst
all age groups of patients.[6] The worldwide prevalence rate of
epilepsy is in the range of 5 per 1000, and India’s prevalence
rate of epilepsy is in the range of 4.15–7.13 per 1000.[7, 8] The
World Health Organization (WHO) estimated that around
50 million individuals throughout the world suffer from epi-
lepsy.[9, 10] About 80% of people with epilepsy live in nations
where the median income is less than $2 a day.[11] As the
third leading cause of mortality in the UK, dementia affects
almost 47.5 million people worldwide. According to WHO
projections, by 2030, there will be over 75.6 million people
living with dementia.[1, 12–14] Epileptic seizures have different
characteristics depending on where in the brain the disrup-
tion begins and how far it goes. Temporary symptoms such as
loss of awareness or consciousness, as well as abnormalities
in mobility, sensation (including vision, hearing and taste),
mood or other cognitive function, can occur. Antiepileptic
drugs, dietary manipulation and surgical excision are major
treatment options for epilepsy. The second most common ND
is migraine, which is the most important and frequently re-
ported condition amongst adults and older patients. People
in the age group of 18–25 are reported to have migraine
headaches. Migraine headaches affect more than 1.7–4% of
adult populations worldwide each month. The long-term ef-
fect of headaches predisposes to other illnesses such as anx-
iety and depression, as well as having a negative impact on the
patient’s quality of life. Antimigraine drugs are prescribed for
subsequent pain management.[6] Neurodegenerative diseases
(NDD) are of global concern because they involve the loss of
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2Nilay Solanki et al.
neurons in the central nervous system, which is the hallmark
of brain dysfunction and impairment. Degenerative neural
tissues are characterized by an abnormal build-up of protein
debris, which leads to inammation and an increased risk of
neurodegenerative damage, which leads to impaired memory,
learning, an altered capacity to adjust behaviour to the envi-
ronment, impaired working memory, apathy, depression, dis-
inhibition and/or a dysexecutive cognitive prole – all clinical
symptoms and shifting functional patterns.[15] Alzheimer’s,
Parkinson’s, Huntington’s and amyotrophic lateral sclerosis
have been associated with comorbidities of neuropsychiatric
symptoms due to a loss of stress resistance and functional im-
pairment of mitochondria. Mitochondrial targeting therapy
can be a good alternative to conventional treatments for
NDD.[16] The prevalence rates for Parkinsonism, Alzheimer’s,
dementia and myasthenia gravis are low; specically, for
Parkinsonism, the prevalence rate is in the range of 71.6 per
100,000, and for Alzheimer’s and dementia, it affects 10–15%
of the population.
Rationale: Pharmacotherapy plays an important role in the
management of these neurological disorders. With this outset,
the present study investigated CNS drug utilization trends,
drug–drug interaction and morbidity patterns for ND at a
multispecialty hospital.
Methodology
The present study was conducted at the Dr. Jeevraj Mehta
Smarak and Health Foundation (JMSHF), a multispecialty
hospital in Gujarat, India. The hospital has a fully equipped
intensive care unit (ICU) facility and a well-maintained out-
patient department (OPD).
Study design
A prospective cross-sectional study was carried out at a multi-
specialty hospital in the neurology outpatient department for
a six-month period (2016–2017). After their informed con-
sent was obtained and the study was explained to them, all
patients with neurological disorders were enrolled in the
study. The study was ethically approved in an Institutional
Ethics Committee (IEC) for Human Research meeting at
the JMSHF with reference number ECR/274/Inst/GJ/2013/
RR-19.
Study criteria
• Inclusion criteria: patients who were treated for a neu-
rological condition and were outpatients in the neurol-
ogy department.
Predicting prescribing trends, indicators and procedures[6,
8, 17, 18]:
• After taking informed consent from patients, the neu-
rology department enrolled them in the study. Patients
were interviewed personally and asked questions re-
lated to the study design, demographic details and
clinical details of a complete prescription that was re-
corded in the case record form. Data were analysed for
prescribing trends, morbidity patterns and drug–drug
interaction patterns in the neurology outpatient depart-
ment. Prescription pattern parameters were analysed ac-
cording to WHO core prescribing indicators; prescribed
medications’ essentiality was determined as per the
WHO essential drug list 2015; they were also coded
according to the Anatomical Therapeutic Chemical
Classication of Drugs (ATC classication); diagnosed
disorders were coded according to the International
Classication of Disease-10 (ICD-10) guideline and po-
tential drug–drug interactions were evaluated by the
Medscape multidrug interaction checker. The data were
statistically analysed with means, percentages, standard
deviations and so on.
• Assessment of drug utilization trends: The prescriptions
were collected from the outpatient department of
the hospital. Records of the prescribing trend-related
parameters such as age, sex, number of prescribed drugs,
drug name (generic and brand) and so on were noted
in the case record form and later analysed as per WHO
criteria.
Assessment of morbidity pattern
• Record and analyse the morbidity factor from the col-
lected prescriptions.
• Code the specic morbidity as per ICD-10.
Drug–drug interactions study procedures
• Collect the prescriptions from the outpatient department,
which contain at least two medicines.
• Refer to the website reference as medscape.com/drug in-
teraction checker.
• Add prescribed drugs one by one.
Result
A total of 280 prescriptions were collected. One hundred
and fty patients (53.57%) were female, and 130 (46.42%)
were male. In the age distribution of patients, the majority
of patients were found in the >50-year-old group (45.71%),
followed by the 31–50-year-old range (39.28%) (Table 1).
Out of all patients (280), 87 (31.07%) cases were diagnosed
Table 1 Demographic distribution of patients
Demographic details N = 280 (%)
Gender
Female 150 (53.57%)
Male 130 (46.42%)
Age
>10 3 (1.07%)
11–30 39 (13.92)
31–50 110 (39.28%)
<50 128 (45.71%)
Previously diagnosed condition
Hypertension 72 (86.74%)
Diabetes 7 (8.43%)
Hypertension + diabetes 4 (4.81%)
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Assessing drug utilization and drug–drug interactions 3
with epilepsy, with partial seizures (64.36%) being the most
common, followed by generalized tonic–clonic (22.98%)
seizures and absence seizures (12.66%). Other than epilepsy,
migraine (30.35%) was a second major neurological condi-
tion, followed by parkinsonism (13.21%), Alzheimer’s and
dementia (10.71%) and myasthenia gravis (10.65%).
In the age distribution of patients, the majority of patients
were found in groups older than 50 years, followed by other
groups. The current study found that the most common neu-
rological disorders were epilepsy (62.21%), Parkinsonism
(56.87%), Alzheimer’s and dementia (42.28%).
Out of 280 patients, 83 (29.64%) had previously been
diagnosed with conditions such as hypertension (86.74%),
diabetes (8.43%) or a combination of both (4.81%). Various
categories of CNS drugs were prescribed for the manage-
ment of neurological conditions such as epilepsy, migraine,
parkinsonism, depression and so on (Figure 1) According
to the International Classication of Disease, neurological
conditions are classied as given codes G0–G99, and all com-
monly prescribed drugs were classied according to their an-
atomical therapeutic classication (Table 2).
Drugs prescribed for epileptic patients: A total of 85% of
cases of epilepsy were on monotherapy; the remaining were
on polytherapy. Conventional antiepileptic drugs prescribed
were 81.59%, of which carbamazepine was most commonly
prescribed (Table 2). Sodium valproate (26.12%) was the
most commonly prescribed medication for epilepsy, followed
by carbamazepine (22.12%), clonazepam (20.13%),
levetiracetam (18.22%) and so on. Sodium valproate and
phenytoin were commonly prescribed for monotherapy. In
polytherapy, sodium valproate is prescribed with antidepres-
sant drugs and supportive drugs like vitamins. In June 2006,
more than 85% of drugs were prescribed as per the NICE
guideline for the management of epilepsy.
Drugs prescribed for migraine patients: monotherapy was
used to treat 70% of migraines, while polytherapy was used
to treat the other 30%. The majority of the patients received
prophylactic treatment for the management of migraine
headaches (Table 2). Amitriptyline (26.08%) and propran-
olol (26.08%) were prescribed to a large number of patients.
A xed-dose combination of naproxen and domperidone
was prescribed in 21.73% of prescriptions for monotherapy.
Prophylactic treatment with amitriptyline and propran-
olol is prescribed in polytherapy. More than 80% of drugs
were prescribed as per National Institute for Health and
Care Excellence (NICE) guidelines for the management of
migraine.
Drugs prescribed for Parkinson’s and Alzheimer’s disease:
Out of the 280 cases that were reported, 37 were linked to
Parkinsonism, which is the most common illness in older people.
For this condition, more than 70% of patients were treated with
a combination drug of levodopa and carbidopa; as many as 30
(10.71%) cases were reported with Alzheimer’s and dementia
and were mainly treated with donepezil (46.33%), while 20
(7.14%) cases were reported with myasthenia gravis and were
treated with pyridostigmine (60.53%). Twenty patients were
Figure 1 Prescribing drug categories in various neurological conditions
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4Nilay Solanki et al.
reported with the myasthenia gravis condition, where pyrido-
stigmine (60.53%) was a highly prescribed drug for this con-
dition, followed by fexofenadine (10.86%) and vitamin More
than 50% of the prescriptions had anticholinesterase-like
drugs like pyridostigmine for the myasthenia gravis condition.
WHO core prescribing indicators: The total number
of prescribed drugs was 732; out of the 95.83% of drugs
prescribed from the WHO essential drug list in 2015, only
4.17% were prescribed irrationally. Prescriptions with
antibiotics and injections were 1.66% and 4.16%, respec-
tively. Only 8% of drugs were prescribed with generic names,
whereas 92% were prescribed with brand names. The present
study reported the average cost of medication per day for
neurological conditions that were reported during the study
period. After analysing the cost for various neurological
conditions, in paralysis cases the highest medication cost
was found other than all ND [30.66 Indian rupees (INR)],
followed by Parkinson’s disease (30.27 INR), myasthenia
gravis (29.74 INR), epilepsy (28.78 INR), Alzheimer’s and
dementia (28.43 INR) and migraine (27.41 INR).
Potential for drug–drug interactions: During the course
of our research, we observed 65 instances of drug–drug
interactions. About 76.78% of all prescriptions have no po-
tential for drug interactions. 16.07% of prescriptions meet
one drug–drug interaction and are followed by others.
Interactions were pharmacokinetic in 84.60% of cases, phar-
macodynamic in 13.37% and unknown in 2.03%. In Table 3,
signicant, minor and serious types of drug–drug interactions
and their mechanisms were mentioned for different combina-
tion therapies.
Discussion
In summary, a total of 280 cases 150 were females and 130
were males. The majority of patients were over 50 years old
(45.71%). The most common neurological conditions were
epilepsy (31.07%) and migraine (30.35%), with epilepsy
being treated mostly with conventional antiepileptic drugs
like sodium valproate and carbamazepine. Migraine patients
were treated mostly with amitriptyline and propranolol. For
Parkinsonism, a combination drug of levodopa and carbidopa
was used for 70% of patients, while Alzheimer’s and de-
mentia were treated mostly with donepezil. A total of 732
drugs were prescribed in 2015, with 95.83% coming from
the WHO essential drug list and only 4.17% being prescribed
irrationally. Sixty-ve drug–drug interactions were reported,
with 76.78% having no potential for interaction. A study on
the prescribing trend was carried out in the neurology outpa-
tient department among all age groups of patients as a con-
tinuation and extension of the previous work on prescribing
trends in Parkinson’s cases.[19]
The WHO’s core prescribing indicators reected overall
prescribing patterns and the rationality of neurological
prescribing. At present, we observe that over 92% of drugs
are prescribed with brand names, and only 8% are prescribed
with generic names. Similar results were obtained in previous
studies conducted by Mohammed Th et al. analysis of patients
according to neurological condition showed that out of 280
patients, most reported having epilepsy (31.07%), followed
by migraine (30.25%), Parkinsonism (13.21%), Alzheimer’s
and dementia (10.71%), paralysis (7.50%) and myasthenia
gravis (7.14%). Similar studies were reported by Bhatt et al.,
who found that out of all the cases, 73.57% were epileptic
and the rest were migraines.[6] The majority of epileptic cases
were in female patients. The most common type of seizure
is a partial seizure, followed by generalized tonic–clonic and
absence seizures, as reported in other studies.[6, 20] The current
study reported an age range of 6–90 years in males and 11–90
years in females. The average age range of the population was
51 years. It was reported that patients who are older than
60 years are more susceptible to neurological disorders, with
67% of patients being in the age group of 50 years, followed
by 31–50 years, which was supported by one scientic study
where the majority of patients were geriatric.[21] In another
study where depression, anxiety and post-traumatic stress
disorder (PTSD) were common, 89% of people reported
having PTSD and 71% had anxiety.[22] Drug therapy is the
chief support for the management of neurological disorders
Table 2 Commonly prescribed medication for various neurological conditions
Sr no Neurological Condition (ICD10 Code) Drugs prescribed (Generic name) ATC code for the medicine Percentage of prescribed medicine
1 Epilepsy (G40) Sodium valproate – 26.12%
Carbamazepine N03AF01 22.12%
Clonazepam N03AE01 20.13%
Pregabaline – 1.16%
Levetriacetam – 18.22%
2 Migraine (G43) Amitriptline N06AA09 26.08%
Naproxen + domepridone G02CC02+A03FA03 21.73%
Propranolol C07AA05 26.08%
Ibuprufen + paracetamol N02BE71 4.34%
Aspirin B01AC06 4.34%
3 Parkinson’s disease (G20) Levodopa + carbidopa N04BA02 70%
4 Alzheimer’s and dementia (G30) Donepezil – 46.3%
Fluoxetine N06AB03 33.33%
Amitriptylin N06AA09 13.33%
5 Myasthenia gravis (G70) Pyridostigmine N07AA02 60.53%
Fexofenidine R06AX26 10.86%
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Assessing drug utilization and drug–drug interactions 5
in the various categories for which drugs are prescribed. In
our study, sodium valproate was commonly prescribed as
monotherapy for the management of epilepsy. Similar results
were shown in the previous study.[6, 23] Another study observed
that phenytoin was commonly used as an antiepileptic drug.
One third of the patients needed more than one drug for ad-
equate seizure control, and the most common add-on drug
was levetiracetam.[17] Amongst them, antiepileptics were
prescribed, mostly supported by past studies.[6, 24] In our
study, both conventional and new antiepileptic drugs were
prescribed for epilepsy management. Newer antiepileptic
drugs cannot be recommended as rst-line agents because of
limited clinical experience and data. In our study, carbamaz-
epine was a commonly prescribed antiepileptic drug, which
was also reported in one scientic study by Vettikkadan et
al.[23] In our study, sodium valproate, phenytoin and carba-
mazepine were frequently prescribed in combination, which
was also reported by Bhatt et al.[6]
The current NICE guidelines observe that sodium val-
proate should be used as a rst-line treatment for tonic–
clonic seizures.[25] Although sodium valproate is an effective
and widely prescribed treatment for epilepsy, it is associated
with foetal hepatic failure in children.[26] In our study, over
85% of drugs were prescribed as per NICE guidelines. In an-
other study, a similar result was obtained.[6] In our study, 85%
of prescriptions utilized monotherapy treatment for epilepsy.
Because of the lower medication costs and lower risk of ad-
verse events, monotherapy is preferred over polytherapy; it
also improves patient compliance.[6]
Other than epilepsy, migraine was commonly found in
the adult age group of patients. Tension-type headaches
were commonly reported during our study period. Various
analgesics and antimigraine drugs were prescribed for the
management of headaches. A previous study found the same
thing. A majority of patients were treated with prophylactic
treatments. According to previous studies, amitryptyline and
propranolol were the most commonly prescribed migraine
medications in this.[27] According to the NICE guideline, for
the preventive treatment of migraine, prophylactics are advis-
able.[28] In addition to analgesics, naproxen with domperidone
was prescribed to a large number of patients to treat migraine
headaches.
Parkinson’s disease was also commonly reported in geri-
atric patients. For the management of this condition, levo-
dopa with carbidopa was prescribed, which was also reported
in previous studies. The NICE guideline also recommends a
combination of levodopa and carbidopa as a rst-line agent
for the management of Parkinson’s disease. Donepezil was
frequently prescribed as a rst-line agent for Alzheimer’s and
dementia (AD). It has a high level of effectiveness against
the symptoms of Alzheimer’s and dementia. Fluextine is also
prescribed in major prescriptions for AD and is a safer drug
than all others. One study conducted by Aboukhatwa et al.
stated that selective serotonin reuptake inhibitors have a pos-
itive role in the treatment of depression.[29] Another study by
Chadwick et al. stated that after treatment with amitriptyline
for patients with dementia, there was a signicant improve-
ment in behavioural abnormalities.[30] A study conducted
by Patel reported that among all drugs, donepezil (68.49%)
was the most frequently used drug for dementia, followed
by rivastigmine (13.63%), lorezepam (23.97%), clozapine
(11.53%) and so on.[31]
According to the international classication of diseases, the
ICD-10 guideline was used to classify diseases in the G0 to
G99 range.[32] Epilepsy (G40), migraine (G43), Parkinson’s
disease (G20), Alzheimer’s and dementia (G30), paralysis
(G80) and myasthenia gravis (G70) were all coded. Tyagi
et al. conducted a similar study and provided codes for the
different conditions according to ICD 10.[33] Another study
conducted by Qudsia et al. also used a coding system for var-
ious diseases according to ICD-10-42, which supported our
study results.
CNS drugs are commonly prescribed for polytherapy,
which is prone to drug–drug interactions (DDIs). DDIs were
observed in major neurological conditions such as epilepsy,
migraine, parkinsonism and so on. Pharmacokinetic types
of interactions (86.40%) were observed with alterations in
absorptions, metabolism and enzyme induction, while phar-
macodynamic types of interactions (13.37%) were observed
with synergism and antagonism. In our study, drug–drug
interactions occurred through the absorption (61.53%)
mechanism, as was most commonly reported. In a previous
study, similar results were obtained. Drug–drug interactions
were observed in 19 medications (aspirin, propranolol, folic
acid, levoodpa, atorvastatine and others) via the absorption
mechanism. From our study, we can interpret that amongst
all prescribed active ingredients, aspirin had a high level of
interaction with all neurological conditions. Similar results
were obtained in previous studies. Another scientic study
observed that patients with high-risk transient ischaemic
attacks who got clopidogrel and aspirin had a lower risk of
major ischaemic episodes but a higher risk of major bleeding
Table 3 Potential for drug–drug interaction observed in neurology
department
Signicant type of drug–drug interactions
Sr.
no
Combination
of drugs
Probable mechanism of actions for DDI
1 Naproxen +
propranolol
Naproxen decreases the effects of propran-
olol by pharmacodynamic antagonism.
2 Levooxacine
+ diclofenac
Risk of CNS stimulation/seizure. Mech-
anism: Displacement of GABA from
receptors in the brain.
3 Carbamaze-
pine + phen-
ytoin
Carbamazepine will decrease the level or
effect of phenytoin by affecting hepatic
enzyme CYP2C9/10 metabolism.
4 Levodopa +
propranolol
levodopa increases the effects of proprano-
lol by pharmacodynamic synergism.
5 Carbamaz-
epine +
clobazam
Concomitant administration can increase
the potential for CNS effects (e.g. increased
sedation or respiratory depression).
Minor type of drug–drug interactions
6 Aspirin + fo-
lic acid
Aspirin decreases levels of folic acid by
inhibition of GI absorption
7 Escitalopram
+ propranolol
Escitalopram increases levels of proprano-
lol by decreasing metabolism.
8 Carbamaze-
pine + phen-
ytoin
Carbamazepine may increase or decrease
phenytoin levels.
Serious type of drug–drug interactions
9 Clonidine +
atenolol
Either increases toxicity of the other by
unspecied interaction mechanism. Can
increase the risk of bradycardia.
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6Nilay Solanki et al.
than those who received aspirin alone.[34] In our study, large
numbers of DDIs were observed in the signicant clinical
class (60.86%). Only 8.69% of drug interactions are severe.
Similar results were obtained from the study conducted
by Patel et al., where, out of 2066 potential drug–drug
interactions, 3.67% were serious and 73.37% were signif-
icant.[35] A parallel result was also obtained from the study
by Abideen, where out of 72 drug–drug interactions, 50%
were reported as minor and the rest were major and signif-
icant. Co-administration of carbamazepine and phenytoin
results in a signicant type of drug interaction, where car-
bamazepine decreases the effect of phenytoin by affecting
the hepatic enzyme Cytochrome P-450-2C9/9 metabolism.
Carbamazepine also interacted with clobazam. Through
co-administration, both of them increased sedation and
respiratory depression. Another example of a drug com-
bination is levodopa and propranolol. In this interaction,
levodopa increased the effects of propranolol through phar-
macodynamic synergy. In the same way, levooxazine and
diclofenac cause signicant drug interactions by dislocating
the GABA receptor in the brain. The co-administration of
escitalopram and propranolol caused a minor drug–drug in-
teraction. In this interaction, escitalopram increased levels
of propranolol by decreasing its metabolism.[36–39] Another
drug combination was carbamazepine and phenytoin. This
carbamazepine–phenytoin DDI resulted in a minor drug
interaction.
Potential message
• Neurological disorders have a signicant impact on the
patient’s morbidity and mortality.
• Polytherapy prescriptions were signicantly high for the
management of Epilpesy, migraine, AD and PD.
Limitation for clinical setting
The present study utilized very specic data sets, and in the
future, a large number of patients should be enrolled with
specic objectives to translate current results into more sta-
tistically signicant ways in terms of developing critical drug
utilization reviews, morbidity, and DDI-related mechanisms
for CNS drugs.
Conclusion
Partial seizures were the most prevalent neurological dis-
order, and sodium valproate was the most commonly
recommended medication. A combination drug of levodopa
and carbidopa was highly prescribed for Parkinson’s disease,
while Alzheimer’s-related dementia was mainly treated with
donepezil. The majority of CNS medications were provided
in accordance with NICE recommendations for the treat-
ment of a wide range of neurological disorders. The pDDI
rises with the use of polytherapy to treat many neurolog-
ical disorders. The ndings of this research have important
implications for clinical practice, including studies of pre-
scription patterns and morbidity as well as the identication
and management of drug–drug interactions in a wide range
of neurological disorders. The audit emphasized the effec-
tiveness of prescription patterns for neurological diseases in
developing countries.
Take-home message
This study provided further insight into our current un-
derstanding of the drug utilization patterns for epi-
lepsy, Alzheimer’s and Parkinson’s diseases and migraine.
Neurological Mobidity ICD10 codes provide interoperability
and data recycling, while reported signicant drug–drug
interactions can give insight into mechanisms that might be
useful in clinical settings and the system at large.
Acknowledgements
The authors are thankful to the Ramanbhai Patel College of
Pharmacy, Charotar University of Science and Technology,
Changa, India for providing the necessary facility and nan-
cial support for the study. The authors are also thankful to
patients and their caregivers for providing necessary informa-
tion due respect to the study.
Conflict of Interests
Declared none.
Data Sharing and Availability Statement
All the important data related to the study were mentioned in
the manuscript only.
Funding
The study was supported by Ramanbhai Patel College of
Pharmacy, Charotar University of Science and Technology,
CHARUSAT Campus, Changa, Gujarat, India. No specic
fund was required for this study.
Ethics Approval Statements
The authors are also thankful to Dr. Jeevraj Mehta Smarak
and the health foundation for IEC approval of the study and
for providing the necessary facility at the hospital with the
number ECR/274/Inst/GJ/2013/RR-19.
Patient Consent
Patient consent was taken prior to the start of the study in an
Informed Consent form.
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