Sustained release dosage forms

Sustained release dosage forms are designed to release a drug at a predetermined rate in order to maintain a constant drug concentration for a specific period of time with minimum side effects. This can be achieved through a variety of formulations, including liposomes and drug-polymer conjugates (an example being hydrogels). Sustained release's definition is more akin to a "controlled release" rather than "sustained".

References

Oral






Ocular / Otologic / Nasal
Urogenital
Rectal (enteral)
Dermal
Injection / Infusion
(into tissue/blood)
Additional explanation:
Mucous membranes are used by the human body to absorb the dosage for all routes of administration, except for "Dermal" and "Injection/Infusion".
Administration routes can also be grouped as Topical (local effect) or Systemic (defined as Enteral = Digestive tract/Rectal, or Parenteral = All other routes).
Routes of administration by organ system
Gastrointestinal
Oral • Buccal • Sublabial • Sublingual • Rectal
Respiratory system
Pulmonary • Nasal
Visual system / Auditory system
Ocular (Ocular-topical / Intravitreal / Transscleral) • Otologic (Oto-topical)
Reproductive system
Intracavernous • Intravaginal • Intrauterine (Extra-amniotic)
Urinary system
Intravesical
Peritoneum
Central nervous system
Intracerebral • Intrathecal • Epidural
Circulatory system
Musculoskeletal system
Skin
Epicutaneous • Intradermal • Subcutaneous