Patient/caregiver was educated on the side-effects of using oxybutynin as follows:
Inhibition of muscarinic receptors in various organ systems
- As oxybutynin is an anticholinergic acting on the muscarinic receptors, it can act on these receptors present diffusely in the body in various organs/systems, thus contributing to various side-effects.
- Oxybutynin use can inhibit the action of acetylcholine on the muscarinic receptors in the brain and spinal cord. Acetylcholine is a major neurotransmitter in the brain and spinal cord, helping with smooth contraction of skeletal muscle and memory. Inhibition of this action of acetylcholine by oxybutynin can compromise motor functions and memory. Oxybutynin use can also contribute to dizziness and drowsiness.
- Acetylcholine acts on the muscarinic receptors in the heart and reduce the heart rate. Oxybutynin, by inhibiting the muscarinic receptors in the heart can contribute to rapid heart rate and tachycardia.
- Oxybutynin use can result in relaxation of smooth muscle of bladder, thus bringing on relaxation of the bladder smooth muscle. This contributes towards preventing random bladder spasms and contractions, thus promoting bladder retention and reducing random episodes of sudden bladder emptying and urinary incontinence. Individuals can present with difficulty to urinate with oxybutynin.
- Oxybutynin, in addition to relaxing the smooth muscle in the bladder, can also relax the smooth muscle of the stomach and intestines, thus contributing to slowing of gastric emptying and bowel movements, gastric retention and constipation.
- Oxybutynin use can result in relaxation and poor contraction of smooth muscle of the salivary and sweat glands. Poor contraction of salivary glands can lead to poor salivation, dry mouth, and thirst. Poor contraction of sweat glands can result in difficulty sweating and cooling off the body in warm environments.
- Oxybutynin use can also result in difficulty draining the fluid in the eye and so, can result in increase in intraocular pressure, headache, exacerbation of symptoms of glaucoma, and contribute to poor vision.
