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19
Genetic and
Developmental
Diseases and
Disorders
Key Terms
Alleles (p. 449)
Atresia (p. 462)
Auscultation (p. 460)
Autosomes (p. 448)
Buccal smear (p. 448)
Congenital anomaly
(p. 452)
Dominant (p. 449)
Epicanthus (p. 469)
Exocrine (p. 469)
Gene (p. 448)
Genotypes (p. 449)
Germ cells (p. 448)
Heterozygous (p. 449)
Homozygous (p. 449)
Karyotyping (p. 448)
Meiosis (p. 448)
Microcephaly (p. 470)
Mitosis (p. 448)
Murmurs (p. 460)
Phenotype (p. 449)
Pyloromyotomy
(p. 464)
Recessive (p. 449)
Somatic (p. 448)
Stricture (p. 460)
Viscous (p. 469)
Learning Objectives
Upon completion of the chapter, the learner should be able to:
1. Define the terminology common to genetic and
developmental disorders.
2. Identify the important signs and symptoms
associated with genetic and developmental
disorders.
3. Describe the common diagnostics used to
determine the type and cause of genetic or
developmental disorders.
4. Identify the common genetic and developmental
disorders.
5. Describe the typical course and management of
the common genetic and developmental disorders.
Overview
G
enetic and developmental disorders can first appear or be diagnosed at any age throughout the life
span. Some are readily diagnosed at birth; others do not display symptoms until childhood, adoles
cence, or adulthood. Although some disorders have relatively few symptoms, others are profoundly disabling
and can even result in early death. In disorders such as cystic fibrosis or Tay-Sachs disease, genetic testing
can inform an individual of whether he or she is a carrier of the disease. There are many other disorders,
however, for which testing is not yet available. ■
447
448 Chapter 19
Anatomy and Physiology
The nucleus of each cell of the human body has 46 chro
mosomes or 23 pairs of chromosomes. Most somatic
(body) cells can reproduce in a process called mitosis
(mi-TOE-sis), during which the 46 chromosomes
duplicate and divide into two identical daughter cells,
each containing 46 chromosomes (Figure 19-1).
Germ cells become haploid cells through a process
called meiosis (my-OH-sis) that results in each cell car
rying only half the number of chromosomes: 23 chro
mosomes (see Figure 19-1). The most common haploid
cells are the ova and sperm cells.
Meiosis is necessary to maintain the normal 46
chromosomes in a newly formed individual. When an
ovum (carrying 23 chromosomes) is fertilized with a
sperm (carrying 23 chromosomes), the newly formed
individual will have a combined total of the normal 46
chromosomes. Half of these, or 23 chromosomes, will
have come from each parent.
Somatic Cell
46 chromosomes
Germ Cell
46 chromosomes
Gametes-
Sperm or Ova
23 chromosomes each
Duplication
92 chromosomes
Division
Meiosis
Identical Daughter Cells
46 chromosomes each
Mitosis
Figure 19-1 Cell division: mitosis and meiosis.
Of the 46 chromosomes each individual cell
possesses, 44 chromosomes, or 22 pairs, determine
somatic or body function and are called autosomes
(auto = self, somes = body). One pair (or two chro
mosomes) are sex chromosomes and determine the
sex of the individual.
Females have XX chromosomes as the sex chromo
some, and males have XY chromosomes. A female germ
cell, or ovum, undergoes meiosis and divides into two
separate X chromosomes; thus, the only chromosome
a female can give is an X, or female, chromosome. Male
germ cells, or sperm, undergo meiosis and divide into
two separate chromosomes, one X and one Y, so the
male can give an X (female) or Y (male) chromosome.
This explains why the male partner, or sperm, deter
mines the sex of the fetus.
If an X sperm combines with the ova, the result
is XX, and the fetus is female. If a Y sperm combines
with the ova, the result is XY, and the fetus is male.
Because each male germ cell division results in one X
and one Y, there is a 50/50 chance of the fetus being
male or female. These two chromosomes, the sex chro
mosomes, are in every cell of the body and are respon
sible for directing the activity of the cell specifically for
a female or for a male.
Chromosomes can be visualized by a process
known as karyotyping (CARE-ee-oh-TYPE-ing),
which involves taking a picture of a cell during mitosis,
arranging the chromosome pairs in order of largest to
smallest, and numbering them 1 through 23.
Sex chromosomes can be evaluated by a simple
buccal smear, performed by obtaining squamous epi
thelial cells from the buccal cavity of the mouth, staining
the cell, and microscopically observing for X chromo
somes called Barr bodies. Barr bodies can be visualized
when two X chromosomes are present (female). If there
is no Barr body, the individual is male.
X chromosomes are much larger than Y chro
mosomes and carry more genetic information. The
X chromosome not only carries genes for female
characteristics but also for other genes essential to
life, such as those for blood formation, various activ
ities of metabolism, and immunity. The Y chromo
some carries only the genes related to maleness and
masculinity.
Chromosomes are made of ultramicroscopic units
of deoxyribonucleic acid (DNA) arranged in a specific
order, each of which is called a gene. Each chromosome
is composed of thousands of genes located at specific
positions in the chromosome.
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Genetic and Developmental Diseases and Disorders 449
Healthy Highlight
Gene Mutations
G
ene mutation is an alternation in the DNA organization that makes up the gene.
Mutations can range from minor, maybe just in a single DNA block, to a large
part of a chromosome. Although most individuals think gene mutations always cause
some abnormality or disease, genes may be able to tolerate mutations in their sequenc
ing. Some mutations are actually helpful, that is, they assist the individual in the adap
tation process. This can help future generations become immune to certain bacteria or
disease processes. So, the mutation might be a healthy alteration. Some alterations in
the gene sequence are inherited from one or both parents and some are acquired during
the individual’s lifetime. There are a variety of types of mutations such as duplication,
deletion, and frameshift mutations. More than 1,100 health disorders are related to
gene mutations, but frequently the body repairs itself using certain enzymes before the
gene is expressed and the altered protein is produced.
Source: NIH: US. National Library of Medicine (2020)
When the chromosomes (one from each parent)
pair up during fertilization of the egg, the genes on the
chromosomes align and are called alleles (ah-LEELS).
This matched gene pair determines heredity or, in other
words, expresses those characteristics inherited from
parents. When we think of genes and heredity, we usu
ally think of facial features such as hair and eye color,
but genes also determine the entire physical makeup of
the individual from the length of toes to the color and
texture of skin.
As discussed in previous chapters, heredity is
thought to play a part in many other processes such as
the development of plaque in arteries and the occur
rence of rheumatic fever, obesity, and alcoholism in
families, to name only a few.
To understand basic heredity, one must look at
individual genotypes—the genetic pattern of the indi
vidual. Each gene in an allele or matched pair of genes
can be dominant (in control) or recessive (lacking con
trol). Dominant genotypes are expressed with a capital
letter (B, for example), whereas recessive genotypes are
expressed with a small letter (b, for example).
If the alleles, or genes in a pair, match, such as BB
or bb, they are said to be homozygous (homo = one,
zygo = yoked or paired). If the alleles do not match,
such as Bb, they are heterozygous (hetero = different,
zygo = yoked or paired).
Expression of a trait such as brown hair or
blue eyes is called phenotype. Generally speaking,
homozygous alleles, whether dominant or recessive,
will always express the trait. Heterozygous pairs
will express the phenotype of the dominant gene
only. Heterozygous pairs are often said to be carriers
of recessive disorders because the recessive trait will
not be expressed unless paired with another recessive
gene (Figure 19-2).
Abnormalities can be due to chromosomal, genetic,
or environmental factors or a combination of these.
Chromosomal disorders are usually related to the num
ber or placement of the chromosome. Chromosomes
can fail to separate properly during cell division, caus
ing one daughter cell to have an extra chromosome and
the other daughter cell to have none.
An abnormal number or structure of autosomal (or
body) chromosomes is usually incompatible with life.
These chromosomes carry a large number of essential
genes, and such major chromosomal abnormalities
usually lead to spontaneous abortion of the fetus. The
most common autosomal chromosomal disorder is
Down syndrome.
An abnormal number of chromosomes in the sex
chromosomes is less serious but does lead to a number
of abnormalities, disorders that are not usually appar
ent until puberty, when sexual characteristics are found
to be abnormal.
An individual can acquire an abnormal gene in
two ways: (1) by mutation of the gene during meiosis,
affecting the newly formed fetus, or (2) by passage of
the abnormal gene from the parents (heredity).
Genetic disorders are passed to offspring in four
ways: autosomal dominant, autosomal recessive, sex-
linked dominant, and sex-linked recessive.
B is dominant for brown eyes
b is recessive for blue eyes
Mother: Bb
Heterozygous
Brown eyed but carrying a
blue recessive gene
Father: Bb
Heterozygous
Brown eyed but carrying a
blue recessive gene
BB Bb
Bb bb
genotype
phenotype
genotype
phenotype
genotype
phenotype
Offspring
1-BB homozygous dominant
Brown eyes
2-Bb heterozygous
Brown eyes
1-bb homozygous recessive
Blue eyes
Figure 19-2 Patterns of dominance.
1. Autosomal dominant Dominant disorders
are easily recognized because presence of the
disorder identifies those individuals with the
dominant gene. The line of inheritance is easily
followed from one generation to another.
Dominant genes will always be expressed,
whether homozygous (PP) or heterozygous
(Pp). An example of an autosomal dominant dis
order is polydactyly, evidenced by an excessive
number of fingers or toes. Refer to Figure 19-3
to see how individuals carrying a dominant
gene (P) would have polydactyly.
2. Autosomal recessive Recessive disorders are
seen only when two recessive genes are paired
(cc). Cystic fibrosis is an autosomal recessive
disorder. Each parent might be phenotypically
normal or without sign of the disorder but be
a heterozygous carrier (Cc) of the disorder. If
each parent is heterozygous, the chance of the
offspring having the disorder is one in four
(Figure 19-4A). If one parent has the disor
der (cc), the chances increase to one in two
(Figure 19-4B). If one parent is homozygous
Polydactyly is dominant (P)
Normal finger number is recessive (p)
Normal mother
P P
P Pp Pp
Polydactyly father
P PP PP
Offspring
genotyPe (all 4) heterozygous
PhenotyPe Polydactyly
Figure 19-3 Autosomal dominant pattern.
dominant (CC), none of the offspring will be
affected (Figure 19-4C).
The occurrence of recessive disorders is often
quite surprising to a family because this disorder
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Genetic and Developmental Diseases and Disorders 451
can skip generations and hundreds of years
before it is paired with another recessive gene
and expressed.
3. Sex-linked dominant Like autosomal domi
nant disorders, these are rarer than the recessive
disorders and are easily recognized.
4. Sex-linked recessive These disorders are typically
carried by females and passed to males. The rea
son for this is that recessive gene disorders on the
X chromosome of the female are overridden by
the dominance of the normal gene on the other
X chromosome.
In males, the X disorder is expressed because
there is no corresponding gene on the Y chro
mosome. X-linked disorders usually appear
every other generation because they are passed
from mother to son (Figure 19-5). The affected
male (son) will pass this disorder to all of his
daughters, who then become carriers.
Genotype Phenotype
cc (affected) cystic fibrosis
CC normal
Cc (carrier) normal
Mother
Normal (carrier)
C c
Father c Cc cc
Has
cystic fibrosis c Cc cc
Offspring
genotype 2-Cc heterozygous (carrier)
phenotype Normal
genotype 2-cc homozygous recessive
phenotype Cystic fibrosis
AUTOSOMAL RECESSIVE
PATTERN
Genotype Phenotype
cc (affected) cystic fibrosis
CC normal
Cc (carrier) normal
Mother
Normal (carrier)
C c
Father C
Normal (carrier)
CC Cc
c Cc cc
Offspring
genotype
phenotype
1-CC homozygous dominant
Normal
genotype 2-Cc heterozygous (carrier)
phenotype Normal
genotype 1-cc homozygous recessive
phenotype Cystic fibrosis
If both parents are heterozygous, there is
a 1 in 4 chance of having a child with
cystic fibrosis.
(A)
If one parent has the disorder, the chances of having a child
with cystic fibrosis increase to 1 in 2.
(B)
AUTOSOMAL RECESSIVE
PATTERN
Genotype
cc (affected)
CC
Cc (carrier)
Phenotype
cystic fibrosis
normal
normal
Mother
Normal (carrier)
C c
Father C.
Normal
(homozygous
dominant)
CC Cc
CC Cc
Offspring
genotype 2-CC homozygous dominant
phenotype Normal
genotype 2-Cc heterozygous (carrier)
phenotype Normal
If one parent is homozygous dominant, none of the offspring
will be affected.
(C)
Figure 19-4 Autosomal recessive pattern.
-------------------------------------------------------------------r
SEX-LINKED
RECESSIVE PATTERN
Hemophilia is recessive X linked
X and Y are chromosomes
H and h are dominant and recessive genes
found only on the X chromosome
XH Xh
Mother
Normal (carrier)
Yo XHYo XhYo
Father
boy boy
Normal
normal hemophiliac
XH XHXH XHXh
girl girl
normal normal (carrier)
Figure 19-5 Sex-linked recessive pattern.
I Unknown Multiple factors
I Mendalian genetic aberration
H Chromosomal Teratogens
Figure 19-6 Causes of congenital anomalies.
The affected male is unable to pass this dis
order to his sons because the male gives a Y
chromosome to sons, not an X. All the carrier
daughters can then pass the disorder to their
sons. If the mother is a carrier (XX Hh), there
is a possibility that some of her sons will not be
affected. If the mother has the disorder (XX hh),
which is very rare with X-linked disorders, all
her sons will have the disorder. Hemophilia and
muscular dystrophy are both sex-linked reces
sive disorders.
Approximately 2% of all newborns have a signifi
cant birth defect, or congenital anomaly (kon-JEN-ih-
tahl; present at birth) (ah-NOM-ah-lee; abnormality).
A high percentage of defects (60%) are due to an
unknown cause.
Other causes are genetic (20%), chromosomal
(10%), and teratogens (ter-AT-oh-gens) or envi
ronmental (10%) (Figure 19-6). Chromosomal and
genetic causes have been discussed. Teratogens include
any chemical, substance, or exposure that can cause a
physical defect in a fetus during pregnancy. Teratogens
are commonly thought of as environmental causes and
include maternal radiation, infection, metabolic dis
orders, smoking, alcohol, drugs, and medications, to
name only a few.
Common Signs and Symptoms
Signs and symptoms of the various genetic and devel
opmental disorders vary, depending on the disorder,
and are discussed individually with each disorder.
Diagnostic Tests
Diagnosis of many of the genetic and developmental
disorders begins with a physical examination of the
affected individual. Diagnostic tests for these dis
orders vary, depending on the disorder. Advanced
genetic testing is becoming more common but there
is some question as to the value versus cost issues.
Some genetic tests can be done using commercially
designed kits or laboratory-developed tests. The diag
nostic tests for the disorders are discussed individually
with each disorder. Prenatal diagnosis of genetic and
developmental disorders can be beneficial for genetic
and family counseling. Tests to diagnose prenatal dis
orders include:
■ Ultrasonography of the fetus to detect malforma
tions of the head, internal organs, and extremities.
■ Amniotic fluid analysis to determine genetic and
chromosomal disorders.
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Genetic and Developmental Diseases and Disorders 453
Complementary and Alternative Therapy
Using Meditation to here are some established research findings supporting the benefits of meditation for
health. Meditation involves the mind and the body. It has been found that it might
ImploVeeall help an individual cope with various illnesses, improve one’s psychological balance, and
improve the quality of life. The National Center for Complementary and Integrative
Health reported what scientific research has demonstrated about meditation:
■
■
■
■
■
■
■
■
Meditation has been shown to help individuals undergoing therapy for cancer. Some
of the side effects can be relieved through meditation such as anxiety, fatigue, sleep
issues, and moodiness.
Meditation may lower blood pressure. The American Heart Association supports
using meditation along with the usual pharmaceutical medicines to reduce high blood
pressure.
Meditation may help with menopausal symptoms. It can reduce the number of hot
flashes, joint pain, and sleep problems.
Meditation can reduce symptoms of anxiety. It may also help with depression, pain,
and distress.
Meditation helps individuals with irritable bowel syndrome (IBS). It has been shown
to help with the pain but not the depression or anxiety associated with the disease.
Meditation has been studied as an adjunct therapy for smoking cessation programs
but there is not enough research-based evidence to state that it is effective.
Meditation has also been studied for its benefits in attention deficit hyperactivity dis
order (ADHD). No conclusions have been drawn about its effectiveness for treatment
in ADHD.
Meditation is considered to be a safe therapy for healthy individuals in general.
Source: National Center for Complementary and Integrative Health (NCCIH) (2021)
■ Maternal blood analysis to observe for abnormal
fetal substances.
Consider This...
Everyone has a unique smell that is deter
mined by genetics, environment, diet, and
personal hygiene.
Common Genetic and
Developmental Disorders
There are hundreds of genetic and developmental dis
orders among populations; however, most of them
occur very rarely.
Genetic or developmental disorders might affect
only one body system or involve several systems. Mus
cular dystrophy, for example, which affects the muscu
loskeletal system, can also be considered a neurologic
system disease because it affects the neurons, thereby
affecting muscle movement.
Some of the more familiar genetic and develop
mental disorders are covered in this chapter.
Musculoskeletal
Genetic and developmental musculoskeletal disorders
are some of the more familiar severe disorders. The
severity of the disease varies with the particular disorder
and other problems the individual has.
Muscular Dystrophy
■ Description. Muscular dystrophy (MD) (dys =
abnormal, trophic = nourishment, growth) is a group
454 Chapter 19
of genetically inherited diseases characterized by pro
gressive degeneration, or weakening, of the muscles.
The affected muscles are unable to store needed pro
tein. Malnourished muscle fibers die and are replaced
with fat and connective tissue. These fibers are unable to
contract and function like muscle fibers. Over a period
of time, the muscle digresses from weak to useless.
■ Description. The most common type of MD is
Duchenne’s MD, also called pseudohypertrophic
(pseudo = false, hyper = excessive, trophic = nourish
ment, growth) MD. The affected muscles appear healthy
and bulging when, in reality, they are bulking up in size
from fat deposits. This bulking of muscle mass is espe
cially noticeable in the calf muscle.
■ Etiology. Duchenne’s MD is a sex-linked disorder
generally passed from mother to son.
■ Symptoms. Onset is usually between the ages of 2
and 5 years. The pelvic and leg muscles are usually
affected first, leading to a characteristic waddling gait,
toe walking, lordosis, and Gower’s maneuver (a char
acteristic way of getting up from a squatting position
that demonstrates the weakness of the pelvic muscles)
(Figure 19-7).
Affected children are usually confined to a wheel
chair by age 9. Life expectancy is usually into the
mid-20s, with death due to respiratory or cardiac
complications.
■ Diagnosis. Diagnosis is made on the basis of physical
examination, muscle biopsy, and electromyography.
■ Treatment. Although there is no cure for MD, phys
ical therapy, orthopedic appliances such as leg braces,
and exercise are quite effective in maintaining mobility
and quality of life.
■ Prevention. There are no preventive measures other
than genetic counseling.
Congenital Hip Dislocation (CHD)
■ Description. CHD is an abnormality of the hip joint,
or acetabulum, resulting in the femoral head, or ball,
slipping out of the normal position. CHD is more com
mon in girls and is usually obvious during the first few
months of life.
■ Etiology. It is thought that this disorder occurs as a
result of (1) improper positioning of the fetus in the
uterus prior to or during birth or (2) the maternal hor
mones, which relax the mother’s pelvic ligaments during
labor, also relaxing the joint ligaments in the infant.
4
Figure 19-7 Gower’s maneuver.
■ Symptoms. The affected infant might exhibit asym
metrical folds of the affected thigh, a difference in
leg length, and limited abduction, called a positive
Ortolani’s sign (Figure 19-8).
■ Diagnosis. Diagnosis is confirmed by physical exam
ination and hip joint X-ray studies.
■ Treatment. Treatment involves closed reduction
(placing the femoral head in proper position) and
maintaining the normal position with a splint or cast for
approximately two to three months. Treatment might
require surgery in older children. The earlier the treat
ment is begun, the better the prognosis.
■ Prevention. Prevention is aimed at prenatal care to
determine the position of the baby in the womb to assess
and treat for possible CHD. The practice of swaddling,
or wrapping the baby’s body tightly in a blanket with
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Genetic and Developmental Diseases and Disorders 455
Figure 19-8 Asymmetrical thigh folds and Ortolani’s
sign in congenital hip dislocation.
Figure 19-9 Talipes equinovarus (clubfoot).
Courtesy of Mark L. Kuss
legs forced into a closed, straight-together position, can
lead to CHD. This position places undue stress on the
hip joints.
Clubfoot (Talipes Equinovarus)
■ Description. Clubfoot, or talipes (talus = ankle, pes =
foot) equinovarus (TAL-eh-peas ee-KWI-no-VAY-rus;
equine = horse or toe walking, similar to a horse, varus =
bent inward), is a frequently occurring congenital defor
mity of the foot.
■ Etiology. The cause of clubfoot is unknown, but it is
thought to be due to genetic factors or fetal position in
the uterus. Some positional deformities can be straight
ened with manipulation, but a true clubfoot deformity
will not straighten with manipulation.
■ Symptoms. The affected foot or feet turn inward with
the toes pointed downward and the heel drawn upward
(Figure 19-9).
■ Diagnosis. Clubfoot is easily diagnosed with physical
examination. X-rays help determine the severity of the
disorder.
■ Treatment. Treatment, quite successful if begun
during infancy, can involve application of a cast
or splints to straighten the foot gradually. The cast
or splints are changed frequently until the desired
position is achieved. If casting and splinting do not
achieve the desired results, surgery might be indicated.
Attention must be given to the position of the child’s
feet throughout childhood to ensure that a normal
position is maintained.
■ Prevention. There are no known preventive measures.
Osteogenesis Imperfecta
■ Description. Osteogenesis (osteo = bone, genesis =
beginning) imperfecta (not perfect or normal) is char
acterized by abnormally brittle bones, often leading to
frequent fractures.
■ Etiology. Osteogenesis imperfecta is an inherited
condition caused by gene mutation.
■ Symptoms. Undiagnosed children affected with
osteogenesis imperfecta might be suspected as vic
tims of child abuse due to the frequency of bone
fractures. Other significant signs are an abnormally
blue coloration of the sclera of the eyes, otosclerotic
deafness, translucent skin, and thin dental enamel of
the teeth.
■ Diagnosis. Diagnosis is made primarily with history
and physical examination. X-rays of the bones can be
helpful.
■ Treatment. There is no cure for osteogenesis imper
fecta, but the tendency of bones to fracture decreases
with age and often disappears by adulthood.
■ Prevention. There are no preventive measures for
osteogenesis imperfecta.
Neurologic
Genetic and developmental neurologic disorders are
some of the most severe because of their long-term
debilitating effects. Two of the most common severe
disorders in this category are hydrocephalus and cere
bral palsy.
456 Chapter 19
Hydrocephalus
■ Description. Hydrocephalus (high-droh-SEF-ah-lus;
hydro = water, cephal = brain) is an abnormal accumu
lation of cerebrospinal fluid in the brain.
■ Etiology. Hydrocephalus is generally caused by
obstruction of the flow of cerebrospinal fluid out of the
brain, which can be from a congenital defect, an infec
tion, or a tumor.
■ Symptoms. The head of the affected child might be
normal at birth but will rapidly enlarge over the first
few months of life as the fluid accumulates. The brain
tissue becomes compressed, and the skull begins to
bulge. Other signs include bulging eyes, a tight scalp,
prominent head veins, and a shrill, high-pitched cry.
The infant is unable to lift its head, fails to develop nor
mally, and is mentally challenged.
■ Diagnosis. Diagnosis is confirmed with skull X-rays
and angiography.
■ Treatment. Treatment of choice is surgical correc
tion by placing a shunt from the brain to the peritoneal
cavity or right atrium of the heart to drain the excess
fluid (Figure 19-10). Even with early surgical interven
tion, the prognosis is guarded. Mortality rate is high
without surgical correction.
■ Prevention. There are no preventive measures.
Microcephaly
■ Description. Microcephaly is a condition where the
head is smaller in circumference than normal because
the brain has not developed or has stopped growing.
Microcephaly may be present at birth or may develop
in the first few years of life.
■ Etiology. This condition may be caused by genetic
abnormalities or by maternal factors. Maternal factors
include the pregnant mother being exposed to certain
toxins, abusing drugs or alcohol, becoming infected
with rubella, varicella, or Zika virus. All these events
may damage the developing brain tissue. With viral-
induced brain injury, there is often brain tissue and cell
death, which leads to the brain actually shrinking rather
than simply not growing.
Common Drugs for Genetic Disorders
Category Examples of Medications
Antibiotics
Drugs used to treat infections Azithromycin, ciprofloxacin, or gentamycin
Antipsychotics
Drugs used to manage psychoses Amantadine, aripiprazole, chlorpromazine,
clonazepam, haloperidol, iloperidone,
lumateperone, quetiapine, pimavanserin, or
risperidone
Antispasmotics
Drugs used to control spasms
and other jerky movements
Reserpine, deutetrabenazine, or tetrabenazine
Mucolytics
Drugs used to aid in the
clearance of mucus
Acetylcysteine, bromhexine, erdosteine,
fudosteine, hypertonic saline, or dornase alpha
Clotting promoters
Drugs to enable the clotting
process
Aminocaproic acid, emicizumab-kxwh,
desmopressin, or tranexamic acid, coagulation
factor IX, coagulation factor XIII A
Others
Additional drugs used for
treatment of some genetic disorders
Eliglustat, glycerol phenylbutyrate, topiramate,
or uridine triacetate
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