Before starting a dog massage treatment, I do a final check to make sure massage can be safely performed. One of my considerations is whether the dog is taking any medications. If so, then I check how the medication is administered (i.e. orally, injection), the frequency with which your dog takes the medication, and when it was last administered. Depending on the answers to these questions, I may need to get a clearance from your vet before massaging the dog.

The reason for these checks is that massage increases blood flow and warms the skin. Both of these factors can affect the rate of drug absorption, distribution and elimination and therefore the effectiveness of the medication. (Goats 1994, Mori et al 2004, Routes 2015)

Massage may affect a medications’ effectiveness in the following three ways.

1. Bioavailability.

This is the fraction of the medication that reaches the circulatory system after it has been administered. Local blood flow is a strong determinant of the bioavailability of a drug to the target tissues. With orally administered drugs, blood from the gut passes through the liver before reaching circulation. The liver is the main site for drug metabolism, this first pass effect may reduce the amount of the drug that reaches the target tissues. (Routes 2015) Increasing blood flow with massage may therefore impact the effectiveness of the drug based on the fraction that reaches the target tissues.

Massage may also increase drug absorption from subcutaneous injection sites and increase plasma concentrations of the drug. It is theorised that massage could increase drug delivery to massaged tissues by increasing the blood flow to these tissues. In a study of human diabetic patients it was found that massaging the area surrounding the insulin injection site improved insulin absorption and may improve its overall metabolism. (Freckmann et al 2012, Ciccone 1995)

2. Volume of distribution.

This is the amount of the drug that appears in the plasma relative to the total amount administered. This parameter is compared to the total body water. In a human, body water is approximately 42 litres. If the volume of distribution is 42 then the drug is distributed uniformly throughout the body tissues. If it is less than 42 then the drug has been retained in the blood stream typically by binding to a constituent like albumin or other plasma protein. If it is greater than 42 then the drug has been stored by binding with extravascular tissue such as skeletal muscle. (Ciccone 1995)

3. Clearance.

This is the rate at which the drug is eliminated from the body. Elimination includes metabolism primarily in the liver and excretion primarily in the kidneys. Elimination can also occur through the lungs, skin or gastrointestinal tract. (Ciccone 1995)

In a study of human patients being treated for thyroid cancer, it was demonstrated that massage assisted in the clearance process by reducing the accumulation of radioisotope in the salivary gland. The salivary glands are highly radio-sensitive so any accumulation can damage them. It is believed that massage “milks” the radioisotope into the oral cavity and in so doing reduces the radiation burden on the salivary gland. (Kim et al 2012)

As massage stimulates the circulatory system, it can affect drug absorption, distribution, metabolism and elimination rates. Before treating your dog, certified canine myofunctional (massage) therapists will consult with you and your vet to ensure that it is safe to proceed with a massage.

When considering massage therapy, it is advisable to check with your vet, if your dog is taking medication regularly. Your vet can advise how best to time your dog’s medication and massage treatments.

Full Stride provides in home and clinic based canine massage and physical therapy services on the north side of Brisbane. Please contact me at jlconlon@fullstride.com.au to find out how massage may benefit your dog.

Until next time, enjoy your dogs.

Sources:

Ciccone, C.D 1995 “Basic Pharmacokinetics and the Potential Effect of Physical Therapy Interventions on Pharmacokinetic Variables” Physical Therapy, Volume 75 : 343 – 351

Freckmann, G, Pleus, S, Haug, C, Bitton, G, & Nagar, R. 2012 “Increasing Local Blood Flow by Warming the Application Site: Beneficial Effects on Postprandial Glycemic Excursions” Journal of Diabetes Science and Technology, Volume 6, Issue 4

Goats, G,C. (1994) “Massage-the scientific basis of an ancient art: Part 2. Physiological and therapeutic effects”, British Journal of Sports Medicine 28 (3) p153 – 156

Kim, H.W, Ahn, B-C, Lee, S-W & Lee, J. 2012 “Effect of Parotid Gland Massage on Parotid Gland Tc-99m Pertechnetate Uptake”, Thyroid Radiology and Nuclear Medicine, Vol 22, No 6.

Mori, H, Ohsawa, H, Tanaka, H, Taniwaki, T, Leisman, G & Nishijo,K (2004) “Effect of massage on blood flow and muscle fatigue following isometric lumbar exercise”, Medical Science Monitor, 10 (5) p173 – 178

Routes, A. E. 2015. “Drug absorption, distribution and elimination; pharmacokinetics.”